Control method, audio device, and information storage medium

ABSTRACT

In a case where a sound of one channel of an audio signal which is reproduced and emitted by a second audio device is emitted from a first audio device, an audio device receives a signal of other channel of the audio signal from the second audio device and causes a sound emission unit to emit a sound of the other channel.

CROSS-REFERENCE TO RELATED APPLICATION

The present disclosure contains subject matter related to that disclosedin Japanese Patent Application JP2015-214389 filed in the Japan PatentOffice on Oct. 30, 2015 and International Patent ApplicationPCT/JP2016/081884 filed in the Japan Patent Office on Oct. 27, 2016, theentire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION Technical Field

The present invention relates to a control method, an audio device, andan information storage medium.

Background Art

There are audio systems where a plurality of reproduction devices suchas audio devices disposed in each room such as a living room or abedroom are connected to a network (home network) such as a LAN andcontrol content reproduction or the like of each audio device iscontrolled using a mobile terminal device (for example, see JP2015-100085 A). In the mobile terminal device, for example, a listscreen of the audio devices is displayed, and a command such as contentreproduction is transmitted to the audio device selected by a user fromthe list screen. In addition, the audio system described in JP2015-100085 A has a configuration in which the user sets a synchronousreproduction group using the mobile terminal device and causes aplurality of audio devices belonging to the same group to perform groupreproduction (synchronous reproduction of same content).

SUMMARY OF INVENTION Technical Problem

There is a demand to regard a plurality of audio devices as one audioapparatus and to emit a sound of an audio signal. That is, there is ademand to emit at least one channel of the audio signal by one audiodevice and to emit at least the other channel of the audio signal byanother audio device. Furthermore, in the above-described audio system,there is also a demand to regard the above-described plurality of audiodevices as one audio apparatus to belong to the group of the groupreproduction, and to emit the audio signal to be reproduced and emittedby another audio device belonging to the same group also in theplurality of audio devices. However, in this case, a distribution pathof the audio signal becomes complicated, and there is a possibility thata delay occurs in a sound emission of the audio signal in the pluralityof audio devices.

An object of the present invention is to reduce the delay in theplurality of audio devices in a case where the group reproduction isperformed in the group including the plurality of audio devicesconsidered as one audio apparatus and one or more other audio devices.

Solution to Problem

An control method according to one embodiment of the present inventionis a control method executed by an audio device and includes: receiving,in a case where a sound of one channel of an audio signal which isreproduced and emitted by a second audio device other than the audiodevice and a first audio device is emitted by the first audio device, asignal of at least other channel of the audio signal from the secondaudio device; and causing a sound emission unit to emit a sound of theother channel.

An audio device according to one embodiment of the present inventionincludes a network communication unit; a sound emission unit; at leastone processor; and at least one memory that stores a plurality ofinstructions, which when executed by the at least one processor, causethe at least one processor to: receive, in a case where a sound of onechannel of an audio signal which is reproduced and emitted by a secondaudio device other than the audio device and a first audio device isemitted by the first audio device, a signal of at least other channel ofthe audio signal from the second audio device via the networkcommunication unit; and cause a sound emission unit to emit a sound ofthe other channel.

An information storage medium according to one embodiment of the presentinvention is a non-transitory information storage medium in which aprogram to be executed by an audio device is recorded, the program forcausing the audio device to receive, in a case where a sound of onechannel of an audio signal which is reproduced and emitted by a secondaudio device other than the audio device and a first audio device isemitted by the first audio device, a signal of at least other channel ofthe audio signal from the second audio device; and cause a soundemission unit to emitting a sound of the other channel.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a configuration of an audio systemaccording to an embodiment of the present invention.

FIG. 2 is a block diagram of a mobile phone functioning as a controlleraccording to an embodiment of the present invention.

FIG. 3 is a block diagram of an audio device according to an embodimentof the present invention.

FIG. 4 is a diagram illustrating an example of a system management tableto be set in the controller.

FIG. 5 is a diagram illustrating an example of an audio control table tobe set in the controller.

FIG. 6 is a diagram illustrating a communication procedure between thecontroller and the audio device.

FIG. 7 is a diagram illustrating communication procedure of thecontroller and the audio device.

FIG. 8 is a diagram illustrating a communication procedure between thecontroller and the audio device.

FIG. 9 is a diagram illustrating a communication procedure between thecontroller and the audio device.

FIG. 10 is a block diagram of two audio devices which are set as astereo pair.

FIG. 11 is a flowchart illustrating stereo reproduction processing(delayed reproduction processing and non-delayed reproductionprocessing) executed by a control unit of the audio device.

FIG. 12 is a flowchart illustrating setting processing of a stereo pairof Rch and Lch executed by the control unit of the audio device.

FIG. 13 is a flowchart illustrating stereo pair cancel processingexecuted by the control unit of the audio device.

FIG. 14 is an explanatory diagram for illustrating a transmission modeof a command between audio devices set as the stereo pair.

FIG. 15 is a flowchart illustrating update processing of reproductionparameter and transmission processing of a reproduction/pause commandexecuted by the control unit of the controller.

FIG. 16 is a flowchart illustrating update processing of reproductionparameter and transmission processing of a reproduction/pause commandexecuted by the control unit of the audio device (a parent device).

FIG. 17 is a flowchart illustrating update processing of reproductionparameter and transmission processing of a reproduction/pause commandexecuted by the control unit of the audio device (a child device).

FIG. 18 is a diagram illustrating an example of control screens (aninitial menu screen, a device selection screen, a source selectionscreen, and a reproduction screen) displayed on the mobile phone.

FIG. 19 is a diagram illustrating an example of the control screens (amaster selection screen and a client selection screen) displayed on themobile phone.

FIG. 20 is a diagram illustrating an example of the control screen (adevice selection screen) displayed on the mobile phone.

FIG. 21 is a diagram illustrating an example of the control screen (themaster selection screen) displayed on the mobile phone.

FIG. 22 is a flowchart illustrating control processing executed by acontroller (the control unit).

FIG. 23 is a flowchart illustrating group setting processing executed bythe controller (the control unit).

FIG. 24 is a flowchart illustrating transmitting processing of groupinginformation executed by the control unit of the controller.

FIG. 25 is a flowchart illustrating the transmitting processing of thegrouping information executed by the control unit of the controller.

FIG. 26 is an explanatory diagram illustrating a transmission mode of anaudio signal between the audio devices belonging to the group at a timeof synchronized reproduction.

FIG. 27 is a diagram illustrating an example of the control screen (thedevice selection screen) displayed on the mobile phone.

FIG. 28 is a flowchart illustrating stereo reproduction operationstopping processing of the controller (the control unit).

DESCRIPTION OF EMBODIMENTS

FIG. 1 is a diagram illustrating a configuration of an audio system 10according to an embodiment of the present invention. The audio system 10includes a plurality of audio devices 4 (4-1 to 4-7) connected via anetwork 9 including a wired LAN 2 and an access point (external accesspoint) 3, and a multi-functional mobile phone (mobile terminal device) 1which functions as a controller 1. Each audio device 4 transmits andreceives the audio signal with each other via the network 9. Thecontroller 1 transmits a command message to the audio device 4 via thenetwork 9.

Each audio device 4 (hereinafter, also referred to as a reproductiondevice and a component device) included in the audio system 10 has awired LAN function and two wireless LAN functions. The audio device 4can activate the access point using one of the two wireless LANfunctions. The access point activated by the audio device 4 is called aninternal access point 4A. The lower audio device 4 is connected to theinternal access point 4A. Generally, the internal access point 4A isoperating in a stealth mode (except during an initial connection, whichwill be described later), so that it is difficult for other device toknow existence of the internal access point 4A. The other wireless LANfunction functions as a child unit of the wireless LAN and is connectedto the internal access point 4A of the upper audio device 4 or anexternal access point 3.

The access point (the external access point) 3 is connected to the wiredLAN 2. The audio device 4-1 is connected to the wired LAN 2 with acable. The audio devices 4-2 and 4-3 are connected to the internalaccess point 4A-1 of the upper audio device 4-1 via the wireless LAN.The audio devices 4-4 and 4-5 are connected to the internal access point4A-2 of the upper audio device 4-2 via the wireless LAN. In addition,the audio device 4-6 is connected to the internal access point 4A-3 ofthe upper audio device 4-3 via the wireless LAN. The audio device 4-7 isconnected to the external access point 3.

In the embodiment, the network 9 is configured by the wired LAN 2 andthe wireless LAN including the external access point and the internalaccess point 4A. For example, Ethernet (registered trademark: IEEE802.3) may be used as the wired LAN and Wi-Fi (IEEE802.11g) may be usedas the wireless LAN. In addition, a distribution server 6 is connectedto the network 9 (the wired LAN 2) via a gateway (not shown) and theInternet 5. The distribution server 6 distributes music data to theaudio device 4.

Each audio device 4 is referred to as a root device, a node device, aleaf device, and a branch device according to the connection form of theaudio device 4 with respect to the wired LAN 2. The root device is theuppermost device connected directly to the wired LAN 2 (via the cable),and the audio device 4-1 is the root device in FIG. 1. The root deviceis the audio device initially registered at the time of construction ofthe audio system 10 and serves as the basis of the audio system 10. Theroot device activates the internal access point 4A for connecting thelower audio device 4 to the network and making it participate in theaudio system 10. All items of music information reproduced by the audiodevice 4 (node device or leaf device) connected to the root device orbelow are transmitted via the root device (the internal access point 4Aof the root device).

The node device is an intermediate device connected to the root device(the internal access point 4A of the root device) via the wireless LAN,and the audio devices 4-2 and 4-3 are node devices in FIG. 1. The nodedevice activates the internal access point 4A for connecting the loweraudio device 4 to the network and making it participate in the audiosystem 10. The music information reproduced by the audio device 4 (leafdevice) connected to the node device or lower is transmitted via thenode device (the internal access point 4A of the node device).

The leaf device is a lower device connected to the node device (theinternal access point 4A of the node device) via the wireless LAN, andthe audio devices 4-4 to 4-6 are the leaf devices in FIG. 1. The leafdevice does not activate the internal access point 4A, but may activatethe internal access point 4A.

The branch device is an audio device 4 which is connected to theexternal access point 3 via the wireless LAN separately from a treehaving the root device as a vertex and which communicates with anotheraudio device 4 in the audio system 10 via the wired LAN 2. The audiodevice 4-7 is a branch device in FIG. 1. The branch device does notactivate the internal access point 4A, but may activate the internalaccess point 4A.

In the audio system, up to two node devices are allowed to be connectedto the root device in order to transmit a high quality audio signal. Inaddition, up to two leaf devices are allowed to be connected to eachnode device. In addition, a hierarchy of connection using the internalaccess point 4A is limited to up to three levels of the root device, thenode device, and the leaf device. Therefore, up to seven audio devicesincluding the root device can be connected via the tree of the wirelessLAN with the root device as the vertex. In the tree illustrated in FIG.1, seven audio devices 4 (4-1 to 4-7) are connected. There is nolimitation on the number of branch devices, but as the control target ofthe controller 1, the number of audio devices 4 in the entire audiosystem 10 is limited to up to ten. However, in the present invention,the maximum number such as the number of hierarchies of the tree, thenumber of the lower devices connectable to each audio device 4, and thelike are not limited to this embodiment.

In addition, each of the audio devices 4-1 to 4-7 is disposed in eachroom of a living room, a dining room, a bedroom, a kitchen, a room A,and a room B in the in-home, for example.

Each of the audio devices 4-1 to 4-7 in the audio system 10 canindependently reproduce different contents. However, in the audio system10, it is possible to make a plurality of audio devices to a group. In aplurality of grouped audio devices, contents supplied from the sameaudio source are synchronously reproduced. The content is, for example,music. The audio source includes a medium such as a CD or a hard diskprovided for each of the audio devices 4-1 to 4-7, music distributionservice by the distribution server 6, or the like. A file format ofmusic data is, for example, MP3, WAV, Sound VQ (registered trademark),WMA (registered trademark), AAC or the like.

In addition, the audio system 10 pairs two or more audio devices out ofthe audio devices 4-1 to 4-7 (sets two or more audio devices out of theaudio devices 4-1 to 4-7 as a stereo pair) and can synchronouslyreproduce different channels of the same content by the paired audiodevices. For example, in a case where the audio devices 4-4 and 4-5 areset as the stereo pair, as the stereo reproduction, the audio signal ofa right channel included in the music data (audio signal) of the samecontent is output from a speaker 65 of the audio device 4-4, and theaudio signal of a left channel is output from the speaker 65 of theaudio device 4-5. The stereo pair setting is processing different fromthe above-described group setting of synchronous reproduction.Hereinafter, the synchronous reproduction in stereo in stereo pairsetting is referred to as “stereo reproduction”, and the synchronousreproduction in group setting is referred to as “synchronousreproduction” for distinction. The group setting and synchronousreproduction will be described later.

The mobile phone 1 functions as an audio system controller (hereinafter,controller) 1 by activating an audio system control program 70 (see FIG.2). The mobile phone 1 (controller 1) communicates with each audiodevice 4 belonging to the audio system 10 via the network 9. Through thecommunication, the controller 1 integrally controls an audio source tobe reproduced by each of the audio devices 4-1 to 4-7 in the audiosystem 10 (For example, which audio device 4 to reproduce which music,which music to distribute to which audio device 4, or the like), avolume, or the like. Further, as the controller 1, the mobile phone 1also performs a group setting for synchronous reproduction.

<Description of Configuration>

Next, the configuration of the mobile phone 1 will be described withreference to the block diagram of FIG. 2. The mobile phone 1 is amultifunctional telephone called a so-called smartphone. The mobilephone 1 has a 3G/4G communication function which corresponds to themobile communication network, a wireless LAN (Wi-Fi) communicationfunction, and a Bluetooth (registered trademark) communication function.By activating the audio system control program 70 which is anapplication program, the mobile phone 1 functions as the controller 1,communicates with the audio device 4 in the audio system via the network9, and transmits a command message corresponding to the operation of theuser to the audio device 4 to control the audio system 10.

The mobile phone 1 includes a control unit 20, an operation unit 30, amedia interface 31, a wireless LAN communication circuit 32, a 3G/4Gcommunication circuit 33, and a Bluetooth (registered trademark)communication unit 34 on a bus 26. The control unit 20 includes a CPU21, a ROM (flash memory) 22, a RAM 23, an image processor 24, and anaudio processor 25. A video RAM (VRAM) 40 is connected to the imageprocessor 24, and a display unit 41 is connected to the VRAM 40. Thedisplay unit 41 includes a liquid crystal display. A standby screen, atelephone number, or the like are displayed on the display. Further, ina case where the mobile phone 1 functions as the controller 1, a screenfor controlling the audio device 4 is displayed. An amplifier 42including a D/A converter is connected to the audio processor 25, andthe speaker 16 is connected to the amplifier 42.

The image processor 24 includes a GPU (Graphics Processing Unit) forgenerating various images such as a standby screen and a telephonenumber. In a case where the audio system control program 70 isactivated, the image processor 24 generates an image of the audiocontroller in accordance with an instruction from the CPU 21, anddevelops the image on the VRAM 40. An image developed on the VRAM 40 isdisplayed on the display unit 41.

The audio processor 25 has a DSP (Digital Signal Processor) for encodingand decoding speech voice. The audio processor 25 outputs the decodedand generated audio to the amplifier 42. The amplifier 42 amplifies theaudio signal and outputs the signal to the speaker 16.

The wireless LAN communication circuit 32 performs wirelesscommunication with the router according to the standard such as IEEE802.11g, and communicates with the audio device 4 via the access point3. The 3G/4G communication circuit 33 performs voice communication anddata communication via a mobile phone communication network. TheBluetooth communication unit 34 communicates with otherBluetooth-compatible device, for example, performs transmission andreception of audio signals, and the like.

The operation unit 30 includes a touch panel 310 (see FIG. 16 and thelike) formed on the display unit 41, and detects a touch operation or aflick operation on the touch panel 310. When the audio system controlprogram 70 is activated, a plurality of operators such as a setup buttonor a scan button are displayed on the display unit 41. The operationunit 30 detects the touch operation performed by the user and acoordinate of the touch position on the touch panel 310, and determineswhich operator is operated.

A memory card 15 is connected to the media interface 31. The memory card15 is, for example, a micro SD card. The audio system control program 70is stored in the memory card 15 or the ROM 22. In the embodiment, asillustrated in FIG. 2, it is assumed that the audio system controlprogram 70 is stored in the memory card 15. The audio system controlprogram 70 may be downloaded via 3G/4G data communication or wirelessLAN data communication, or may be stored in the ROM 22 or the memorycard 15 in advance. In addition, in the memory card 15, a storage area71 for storing a configuration of the audio system (a system managementtable, an audio control table, or the like to be described later) isset.

In the ROM 22, a basic program for executing a call with the mobilephone 1 and an application program are stored. In addition, the ROM 22is a flash memory, and it is also possible to store not only the basicprogram but also downloaded application programs or the like. In the RAM23, a work area to be used when the CPU 21 executes the audio systemcontrol program 70 is set.

Next, the configuration of the audio device 4 will be described withreference to FIG. 3. The audio device 4 includes a control unit 50, anaudio processing unit 51, the speaker 65, an operation unit 59, a memory60, a lighting circuit 61, and an LED 62, and also includes two wirelessLAN communication units (RF modules) 56 and 57 and a wired LANcommunication unit 58. The operation unit 59 has a connect button 59A, areproduction/pause button 59B, a volume up button 59C and a volume downbutton 59D. The control unit 50 includes the CPU and the memory andstores an audio system program 50A. The audio system program 50A may besupplied to the audio device 4 by being read from an information storagemedium such as the memory card or may be supplied to the audio device 4by being downloaded via the data communication. The control unit 50controls the operations of the audio processing unit 51, the wirelessLAN communication units 56 and 57, the wired LAN communication unit 58,and the lighting circuit 61 based on the audio system program 50A.Further, when the connect button 59A is pressed, the control unit 50executes the initial connection operation, which is an operation forconnecting the audio device 4 to the network (the audio system 10).Detailed description of the initial connection operation is omitted.

Further, when the reproduction/pause button 59B is pressed, the controlunit 50 controls the audio processing unit 51 and the like to executethe reproduction operation of the audio source. In addition, when thevolume up button 59C or the volume down button 59D are pressed, thecontrol unit 50 controls the audio processing unit 51 to up or down thevolume of the audio source. In addition, when the reproduction/pausebutton 59B and the volume up button 59C are simultaneously pressed long(for example, pressed for 3 seconds), the control unit 50 executesstereo pair setting for Rch (right channel). Furthermore, when thereproduction/pause button 59B and the volume down button 59D aresimultaneously pressed long (for example, pressed for 3 seconds), thecontrol unit 50 executes stereo pair setting for Lch (left channel). Thestereo pair setting will be described later.

In addition, by executing the audio system program 50A, the control unit50 also functions as a synchronous reproduction controller that servesas a master for controlling synchronous reproduction of contents.

The wireless LAN communication unit 56 performs wireless communicationwith the external access point 3 or the internal access point 4A of theupper audio device 4 according to the wireless LAN standard such as IEEE802.11g. The other wireless LAN communication unit 57 is activated as anaccess point (internal access point 4A) and relays (connects) otheraudio devices (for example, audio devices 4-2, 4-3, and the like) to thewired LAN 2. In addition, when the audio device 4 is initialized, thewireless LAN communication unit 57 is activated as a temporary accesspoint for initial connection and communicates with the controller 1 (themobile phone 1). The operation at the initial connection will bedescribed later. The two wireless LAN communication units 56 and 57 maybe realized by operating one piece of hardware in a time divisionmanner. The wired LAN communication unit 58 has a cable connector andperforms communication via the wired LAN 2 and the access point 3according to a communication standard such as IEEE 802.3. The controller(the mobile phone) 1 is connected to the access point 3, and the controlunit 50 communicates with the controller 1 via the network 9, transmitsan operation state, and receives a command message.

SSID and password of the internal access point 4A are character stringswhich can be obtained from a MAC address of the wireless LANcommunication unit 57. For example, an octet representation of the MACaddress may be set as the SSID and the lower 3 octets (model 1D+serialnumber) may be set as the password. Accordingly, the audio device newlyparticipating in the audio system can find the internal access point 4Abased on the SSID, that is, based on the vendor ID and the model ID ofthe MAC address. Further, the audio device newly participating in theaudio system can generate a password by itself and connect to the foundinternal access point 4A. Accordingly, it is possible to omit the user'sinput of SSID and password in a case of connecting to the internalaccess point 4A. The method of generating the SSID and password of theinternal access point 4A is not limited to the above.

The audio processing unit 51 includes a tuner 52, an audio circuit 53, abuffer 54, and a power amplifier 55. The tuner 52 receives the audiosignal from FM broadcasting or the Internet and inputs the audio signalto the audio circuit 53. The audio circuit 53 performs processing suchas equalization and volume adjustment on the input audio signal.

Further, during the stereo pair setting is made effective, the audiocircuit 53 separates the Rch or Lch audio signal from the input audiosignal for stereo reproduction with the other audio device 4 to bepaired. For example, in a case where the audio device 4 is set to Rch inthe stereo pair setting, the audio circuit 53 separates the Rch audiosignal from the input audio signal.

Then, the audio circuit 53 outputs the processed audio signal to thepower amplifier 55 via the buffer 54 or not via the buffer 54. It isdetermined whether the processed audio signal is output via the buffer54 or not based on the affiliation state of the synchronous reproductiongroup (master and client setting) and the state of the stereo pairsetting (parent apparatus and child apparatus setting) of the audiodevice 4. Details will be described later.

The buffer 54 is a memory for temporarily storing the audio signal, anddelays the output to the power amplifier 55 for a predetermined timeduring the stereo pair is set to synchronize the reproduction with oneor more other audio devices 4 to be paired. The communication delay timewith one or more other audio devices 4 in the audio reproduction is setas the delay time.

The power amplifier 55 amplifies the input audio signal and outputs itto the externally connected speaker 65. The speaker 65 is a monauralspeaker, for example, and emits a sound of an input audio signal.

In addition, the audio circuit 53 can output the processed audio signalto communication units 56, 57, and 58 so as to transmit to another audiodevice 4 for synchronous reproduction or the like. Furthermore, theaudio signal transmitted from the another audio device 4 for synchronousreproduction or the like is input to the audio circuit 53 via thecommunication unit 56, 57, or 58.

The memory 60 is, for example, an EEPROM and stores device information(device name, MAC address and IP address of the wireless LANcommunication unit, installation location, pairing information, groupinginformation, or the like) of the audio device 4 itself, systeminformation (system management table: see FIG. 4), reproductionparameters, and the like. The device name includes “device name” writtenwhen the device is shipped.

The pairing information (relationship information between devices) isinformation on stereo reproduction with anther audio device 4 which isset as the pair. Specifically, the information includes information onpresence/absence of pairing, parent-child information, reproductionchannel information (Rch/Lch). The parent-child information includesinformation specifying whether the device itself is a parent device or achild device, and information specifying another audio device to bepaired. For example, an IP address is used as the information forspecifying another audio device. The reproduction channel is informationfor specifying the reproduction channel (Rch/Lch) of the audio signalreproduced by the audio device itself. The reproduction parameter issetting information concerning reproduction by each audio device 4. Forexample, setting information such as an equalizer and a volume set bythe controller 1 and transmitted to the audio device 4 is included.

The setting of the parent device and child device in the presentembodiment is determined based on the connection position of each audiodevice 4. Priorities are associated with the connection positions. Inthe embodiment, in the descending order of priority, they are a route(wired connection), a branch (router connection such as an accesspoint), a node, and a leaf. In a case where the priorities are equal,for example, the audio device 4 of Rch setting may be used as the parentdevice. Further, the priority order may be appropriately set, andsetting of the parent device and the child device may not be performedbased on the priority order.

The grouping information is information on the synchronous reproductiongroup. Specifically the information includes presence/absence of groupsetting, and the master and client information. The master/clientinformation includes information specifying whether the device itself isthe master or a client of synchronous reproduction, and informationspecifying the master and the client. The information specifying themaster and the client is, for example, an IP address. The master andclient will be described later.

The lighting circuit 61 turns on the LED 62. For example, the lightingcircuit turns on the LED 62 during activation of the audio device 4 andinforms the user of the activation state. In the present embodiment,while activating the audio device 4, by pressing only thereproduction/pause button 59B long (for example, 3 seconds), lightingfor notifying the reproduction channel of the stereo pair setting of theaudio device 4 is performed. In a case of the Rch setting, the LED 62blinks with a short blinking interval, and in the case of the Lch, theLED 62 blinks at a longer blinking interval than in the case of the Rch.The control unit 50 controls the blinking operation based on the stereopair setting information described above.

The audio devices 4-1 to 4-7 may be different devices, but the basicconfiguration of the communication function and the audio signalprocessing function is as illustrated in FIG. 3.

<Description of Table>

FIGS. 4 and 5 are diagrams illustrating an example of a table formanaging the audio system 10. FIG. 4 is a system management table formanaging the connection state of each audio device 4 in the network 9.FIG. 5 is an audio control table for managing the operation of eachaudio device 4 in the audio system 10. The system management table ismainly used by a root device 4-1 to manage the network connection. Inaddition, the audio control table is mainly used by the controller 1 tocontrol the reproduction of the audio source.

The system management table stores the connection state of each audiodevice 4 (component device) included in the audio system 10. The systemmanagement table is generated by the controller 1 when the audio system10 is constructed. In addition, in a case where a new audio device 4 isadded to the audio system 10, the controller 1 updates the systemmanagement table to perform the addition of the audio device 4. Thesystem management table generated or additionally updated is transmittedfrom the controller 1 to the root device 4-1. Thereafter, during theoperation of the audio system 10, each time a disconnection orreconnection of any of the component devices occurs, disconnection orreconnection is detected by the root device 4-1, and the contents of thesystem management table are updated. In addition, the root device 4-1periodically transmits all or a part of the contents of the systemmanagement table as system information to each component device and thecontroller 1. Accordingly, each component device and the controller 1can always hold the latest system information. The detailed operation ofthe transmission of the system information will be described later.

The system management table is identified by the system ID (notdescribed in detail) assigned to each audio system 10. Each componentdevice stores information of the MAC addresses of the upper side (childdevice side) and lower side (internal access point side) (that is, theMAC addresses of the wireless LAN communication units 56 and 57), the IPaddresses of the upper side and the lower side (that is the IP addressesof the wireless LAN communication units 56 and 57), number of connectionstages from the root device 4-1 (HOP number), presence/absence ofactivation of the internal access point, the number of the lower devicesconnected to the internal access point 4A (the number of the childdevices), and or the like corresponding to the device ID of each device.

Although each component device has a separate IP address, the audiosystem 10 has a multicast address set as a multicast group. Bytransmitting the IP packet of the above system information to themulticast address, all of the component devices in the audio system 10can receive this system information packet. The system informationpacket may be transmitted to the IP address of each component device byunicast, but the load on the network 9 can be reduced by multicasttransmission.

In the audio control table of FIG. 5, the upper side address (the IPaddress of the wireless LAN communication unit 56), the model, theinstallation location, the grouping, the pairing, the service, andvarious setting information of the component device are storedcorresponding to the device ID of each device. Each section of the audiocontrol table and each section of the system management table areassociated with each other by the device ID. The controller 1 generatesa control screen (see FIGS. 16 and 17) based on the contents of theaudio control table, and receives control of each component device bythe user. The controller 1 periodically transmits all or a part of thecontents of the audio control table as setting information to eachcomponent device. As a result, each component device can always hold thelatest setting information.

The model information is information (for example, text data) of thedevice name of the audio device 4. The installation location informationis information for specifying the room where the audio device 4 isinstalled. The grouping information is information on a group to whichthe audio device 4 belongs, and indicates a group for theabove-mentioned synchronous reproduction of content. In the embodiment,only one group is set. In addition, the audio device 4 belonging to onegroup is set to either the synchronous reproduction master (masterdevice) or the synchronous reproduction client (client device).

The synchronous reproduction master is in charge of supplying the audiosource to the whole group and controlling synchronous reproduction, andthe synchronous reproduction master itself also functions as one deviceof synchronous reproduction. The synchronous reproduction clientreproduces the content according to the instruction of the synchronousreproduction master. For example, “1A” illustrated in FIG. 5 indicatesthe audio device 4 belonging to the group as the synchronousreproduction master. In addition, “1B” indicates the audio device 4belonging to the group as a synchronous reproduction client. The audiodevice 4 other than the audio devices 4 with “1A” and “1B” is the audiodevice 4 not belonging to the group. As described above, the group canbe formed by operating the controller 1 to set the master, the client,or the like in a device unit. Details will be described later.

The pairing information is information on two audio devices 4 to bepaired to perform stereo reproduction. Specifically, information onpairing number, parent-child relationship, and the reproduction channel(Rch or Lch) is registered. The pairing number is a number forspecifying which audio device 4 is subjected to pairing. Theparent-child relationship is information for specifying which of the twoaudio devices 4 to be paired is the parent device or the child device.The reproduction channel is information specifying which one of the twoaudio devices 4 to be paired to reproduce the Rch audio signal or theLch audio signal. In the present embodiment, these items of informationare described as numerical information in the order of (the pairingnumber, the reproduction channel, and the parent-child relationship). Inthe operation of the controller 1, a plurality of audio devices (twoaudio devices) that are paired are treated as one audio apparatus.

When the stereo pair is set between the audio devices 4, the pairinginformation included in the audio control table is updated based on thepairing information acquired at the time when the controller 1 performsa polling of each device.

The service information is information on an audio source that can bereproduced by an audio device, and includes a CD (CD player), a radio(including FM broadcasting, net radio), net distribution, or the like.The net distribution is a function that the audio device 4 accesses thedistribution server 6 of the music distribution service via the Internet5 and downloads and reproduces the audio data of the music (content)selected by the user by streaming.

The various setting information includes various setting informationitems such as reproduction parameters of each audio device 4. Thereproduction parameter is setting information concerning reproduction byeach audio device 4. For example, setting information of the equalizerand volume is included. In the parent device and the child device set asthe stereo pair, since the reproduction parameters of the parent deviceare common reproduction parameters, the reproduction parameters of theparent device and the child device have the same contents.

In the case of constructing the audio system 10, the root device 4-1 isfirst set by the control application executed in the controller 1 toconstruct the audio system 10. Thereafter, the audio devices 4 otherthan the root device 4-1 are added to the audio system 10. The useroperates in the following procedure. The user connects the audio device4-1 that functions as the root device to the wired LAN 2 with the cable.The user activates the controller 1 in a setup mode on the mobile phone1. The user presses the connect button 59A of the audio device 4-1according to the instruction of the screen of the controller 1. If theuser performs the above-described operations, the controller 1 and theroot device 4-1 communicate with each other, and the audio system 10 isautomatically constructed. Thereafter, in a case of adding a new audiodevice 4 to the audio system 10, if the user activates the controller 1in the setup mode, turns on the power of the audio device 4 to be added(activates the wireless LAN communication units 56 and 57), and pressesthe connect button 59A, the audio device 4 communicates with thecontroller 1 and the root device 4-1. In this case, the audio device 4is automatically added to the audio system 10 by automaticallygenerating a password from the above SSID.

<Description of Audio System Construction Procedure>

The communication procedure between the controller 1 and the audiodevice 4 when constructing the audio system 10 or adding the audiodevice 4 to the audio system 10 will be described with reference toFIGS. 6 to 9.

FIG. 6 is a diagram illustrating a communication procedure between thecontroller 1 and the audio device 4-1 that functions as the root devicein the case of newly constructing the audio system 10. The audio systemcontrol program 70 (application) is activated on the mobile phone 1, andthe mobile phone 1 functions as the controller 1. When the controller 1becomes the setup mode according to the operation of the user (S31), aguide screen prompting the user to press the connect button 59A of theaudio device 4 is displayed on the display unit 41. According to theguidance on the screen, the user presses the connect button 59A of theaudio device 4-1 (S41). Next, the controller 1 searches for a new audiodevice connected to the wired LAN 2 (S32). This search is performed bytransmitting a message requesting a response such as polling. The audiodevice 4-1 responds to the search (S42). As a result, the controller 1and the audio device 4-1 start intercommunication via the wired LAN 2and the access point 3.

The audio device 4-1 transmits its own device information (MAC address,IP address, or the like of the wireless LAN communication unit) to thecontroller 1 (S43). The controller 1 constructs a new audio system 10 inwhich the audio device 4-1 serves as the root device. A system ID isassigned to the audio system 10 (S34), a system management table and anaudio control table illustrated in FIGS. 4 and 5 are created, and anaudio system 10 in which the audio device 4 currently communicating withthe controller 1 serves as the root device is constructed (S35). Whenthe audio system 10 is constructed, the system management table istransmitted to the audio device 4-1 serving as the root device (S36),and the setup mode is ended (S37). The audio device 4-1 receives thesystem management table (S44) and saves the table (S45). As a result,the audio system 10 in which the audio device 4-1 serves as the rootdevice which is the key constituent element (component) is constructed.Thereafter, the controller 1 controls the music reproduction and thesound volume thereof. The audio device 4 activates the access point inthe stealth mode (S46).

FIG. 7 is a diagram illustrating a communication procedure in a casewhere a new audio device is added to the constructed audio system 10.The component device is the audio device 4 which is already aconstituent element of the audio system 10. Here, the component deviceis the root device or the node device which activates the internalaccess point 4A. The new device is the newly added audio device 4 fromnow on.

When the mobile phone 1 functioning as the controller 1 becomes thesetup mode by the user's operation (S51), the guide screen prompting theuser to press the connect button 59A of the audio device 4 (new device)is displayed on the display unit 41. According to the guidance on thescreen, the user presses the connect button 59A of the new device (S71).The controller instructs the component device which is the alreadyregistered audio device 4 to cancel the stealth mode of the internalaccess point 4A (S52). As a result, the component device cancels thestealth mode of the internal access point 4A, transmits a beacon frameinforming of the existence of the internal access point 4A to enablepassive scanning by the new device (S61). Next, the controller 1 startssearching for a new device (S53).

When the user presses the connect button 59A (S71), the new devicebecomes the initial connection mode, and searches a connectable accesspoint (passive scan) (S72). In this search, the new device finds theinternal access point 4A of the component device as a connectable accesspoint. As described above, the internal access point 4A has an SSIDallowing the new device to identify the device as the device in theaudio system 10, and the new device can generate a password based on theSSID (or MAC address) and connect to the internal access point 4A. Thenew device selects the nearest internal access point 4A (the easiest toconnect) from the found internal access points 4A and temporarilyconnects to the selected internal access point 4A using the SSID and thegenerated password (S73). This connection is a temporary connection foracquiring the system information and is not a regular connection forparticipating in the audio system 10. The new device acquires thecurrent system information of the audio system 10 from the connectedinternal access point 4A (component device) (S62 and S74). The systeminformation is information including the contents of all or a part ofthe system management table, and is periodically updated by the rootdevice 4-1 and distributed to other component devices. Based on theacquired system information, the new device selects an optimum accesspoint to participate in the audio system 10 (S75). This selection isperformed based on a radio field intensity of each access point, thenumber of connection stages from the root device 4-1, the number ofcomponent devices connected to the access point, or the like, and theaccess point with good communication conditions is selected.

In the example of FIG. 7 (an example in which S100 is not executed), theflow is illustrated in a case where it is determined that thetemporarily connected internal access point 4A is optimal in the regularconnection and the connection destination is not changed. For example,it corresponds to the case where the new device connects to the internalaccess point 4A-1 of the root device 4-1, and the like. In a case wherethe connection destination in the regular connection is changed from thetemporarily connected internal access point 4A, the procedure of FIG. 8or 9 is executed in the section of S100 illustrated in FIG. 7. When theregular connection is completed (after setting the temporary connectionas the regular connection in the case of FIG. 7), the new devicereceives the new device search message from the controller 1 (S53) andresponds to the message (S76). In this way, the new device cancommunicate with the controller 1. As a result, the music to bereproduced in the new device, the sound volume thereof, and the like arecontrolled by the controller 1, and the new device becomes theconstituent element (the component) of the audio system 10.

The new device transmits its own device information (MAC address, IPaddress, allocation location, or the like of the wireless LANcommunication unit) to the controller 1 (S77). The controller 1 receivesthis device information (S54), and registers the new audio device 4 inthe system management table and the audio control table to update thesetables (S55). The controller 1 transmits the updated system managementtable to the root device 4-1 (S56), and ends the setup mode (S57). Theroot device 4-1 periodically distributes system information includingthe contents of all or a part of the system management table to othercomponent devices as a connection confirmation message. The notificationof the end of the setup mode is transmitted from the controller 1 to allthe audio devices 4. However, the controller 1 may transmit thenotification to the root device 4-1 and the root device 4-1 may transferthe notification to the other audio device 4 of the audio system 10.

The new device that has received the system information from the rootdevice 4-1 saves this system information (S78). Thereafter, the newdevice activates the internal access point 4A in the stealth mode (S79).In addition, the component device that has received the systeminformation from the root device 4-1 updates the system informationstored internally with the information (S63). The internal access point4A of the component device is returned to the stealth mode (S64). By theabove processing, a new device can be added to the constructed audiosystem 10. Regarding both the component devices and the new devices, theinternal access point 4A is set up in the stealth mode only in the rootdevice and the node device. Accordingly, the processes of S64 and S79are not performed in the leaf device and the branch device.

FIG. 8 is a diagram illustrating a communication procedure in a casewhere the new device disconnects the temporary connection with theinternal access point 4A in S75 and reconnects to the other internalaccess point 4A in the tree. When the other internal access point 4A isselected as the connection destination of the regular connection in S75of FIG. 6, the new device disconnects the present temporary connectionwith the internal access point 4A (S81) and makes the regular connectionto the selected internal access point 4A, using the address informationin the system information (S82). Thereafter, the process proceeds to S76of FIG. 7.

FIG. 9 is a diagram illustrating a communication procedure in a casewhere the new device disconnects the temporary connection with theinternal access point 4A in S75 and reconnects to the external accesspoint 3 as the branch device. When the external access point 3 isselected as the connection destination of the regular connection in S75of FIG. 6, the new device disconnects the present temporary connectionwith the internal access point 4A (S91), and activates the temporaryaccess point only at the time of the initial connection in thestand-alone mode (S92). That is, the internal access point 4A which isnot connected to the wired LAN 2 but only connected to the new device isactivated. The controller 1 previously stores the SSID and the passwordof the temporary access point for the initial connection. That is, theSSID and the password are written in advance in the audio system controlprogram 70 as data. Accordingly, the controller 1 finds the temporaryaccess point in the new device search started in S53, cancels theconnection with the external access point 3 once, and connects to thetemporary access point activated by the new device (S83). In this case,since there is a high possibility that the SSID and the password of theexternal access point 3 cannot be acquired from the system program ofthe mobile phone 1, the controller 1 requests the user to input the SSIDand the password of the external access point 3 (S84). The input of theSSID may be a method of displaying a list of connection destinations(SSID) that are found at that time on the display and prompting the userto select the SSID of the external access point 3. The password(generally written on the main body of external access point 3) is to beinput by the user.

The input connection information is transmitted to the new device inwhich the temporary access point is activated (S85). The new devicereceives the connection information (S93). After transmitting theconnection information (SSID and password) of the external access point3 to the new device, the controller 1 cancels the connection with thetemporary access point (S86). When receiving the connection informationof the external access point 3 from the controller 1, the new devicedisactivates the temporary access point (S94). The controller 1reconnects to the external access point 3 once disconnected (S87). Thenew device also connects to the external access point 3 using theacquired connection information (S95). Thereafter, returning to theprocedure of FIG. 7, the controller 1 performs new device search (S53),and the new device responds to the search (S76). In a case where theconnection information of the external access point 3 is included in thesystem information acquired from the temporarily connected componentdevice, the processing (S83 to S87 and S92 to 94) indicated in S101 maybe omitted, and the reconnection to the external access point 3 may bemade in the same manner in FIG. 8.

<Description of Stereo pair Reproduction Procedure>

Next, stereo pair reproduction will be described with reference to theblock diagram of FIG. 10. In FIG. 10, as exemplified in FIG. 4, theaudio device 4-4 is the parent device and the Rch setting, and the audiodevice 4-5 is the child device and the Lch setting. Hereinafter, theaudio device 4-4 and the audio device 4-5 may be referred to as theparent device 4-4 and the child device 4-5. The parent device 4-4 andthe child device 4-5 are in a state not belonging to the synchronousreproduction group.

In the stereo pair reproduction, the parent device 4-4 reproduces theaudio signal of its own audio source (content). Hereinafter, a case ofperforming a stereo pair reproduction of an audio signal of FMbroadcasting as an audio source of the parent device 4-4 will bedescribed. The audio signal of the FM broadcasting includes audiosignals of two channels of Rch and Lch. Hereinafter, an audio signalincluding two-channel audio signals may be referred to as an audiosignal (R/L), and only one-channel audio signal may be referred to as anaudio signal (R) or an audio signal (L).

In the parent device 4-4, the audio circuit 53 that has received theaudio signal (R/L) from the tuner 52 performs processing such asequalization and volume adjustment on the input audio signal (R/L).Then, the audio circuit 53 of the parent device 4-4 separates the audiosignal (R) of Rch from the audio signal (R/L) and outputs the separatedsignal to the buffer 54. In addition, the audio circuit 53 of the parentdevice 4-4 outputs the audio signal (R/L) that is not separated to thewireless LAN communication unit 56. The wireless LAN communication unit56 of the parent device 4-4 transmits the audio signal (R/L) to thechild device 4-5 (the wireless LAN communication unit 56).

The wireless LAN communication unit 56 of the child device 4-5 outputsthe received audio signal (R/L) to the audio circuit 53. The audiocircuit 53 of the child device 4-5 separates the Lch audio signal (L)from the audio signal (R/L), and outputs the separated signal to thepower amplifier 55 without via the buffer 54.

In the parent device 4-4, the output timing from the speaker 65 of theaudio signal (R) is synchronized with the output timing from the speaker65 of the child device 4-5 by the delay by the buffer 54. That is, thedelay is caused by the buffer 54 for the same time as the delay time(predetermined time) due to the transmission of the audio signal fromthe parent device 4-4 to the child device 4-5. As a result, the Rch andLch sounds are synchronously output from the speakers 65 and 65 of theparent device 4-4 and the child device 4-5. In the stereo reproduction,the reproduction via the buffer 54 is referred to as delayedreproduction, and the reproduction without via the buffer 54 is referredto as non-delayed reproduction.

FIG. 11 illustrates a flowchart illustrating the above-described stereoreproduction processing. FIG. 11(A) is a flowchart of the delayreproduction processing of the parent device 4-4, and FIG. 11(B) is aflowchart illustrating the non-delayed reproduction processing of thechild device 4-5. The stereo reproduction processing is executed, forexample, in a case where the user operates the controller 1 and theparent device receives a reproduction operation command of thedesignated audio source from the controller 1. As will be describedlater, the child device that is set as the stereo pair is not displayedon the device selection screen of the controller 1, and excluded as atarget of the reproduction operation.

In the same manner as described above, the stereo reproductionprocessing will be described, using the example in which the audioapparatus 4-4 is the parent device 4-4 (Rch), the audio device 4-5 isthe child device 4-5 (Lch), and the stereo audio source (audio signal)of the FM broadcasting of the parent device 4-4 is reproduced.

The parent device 4-4 receives the audio signal (R/L) of FM broadcasting(step S110) and distributes the received signal to two signals (stepS111). Next, the parent device 4-4 separates the Rch from one of thedistributed audio signals (R/L) and transmits the received audio signal(R/L) to the child device 4-5 without channel separation (Step S112).The parent device 4-4 outputs the separated audio signal (R) to thepower amplifier 55 via the buffer 54 (step S113).

On the other hand, the child device 4-5 receives the audio signal (R/L)from the parent device 4-4 (step S120) and separates the Lch from theaudio signal (R/L) (step S121). The child device 4-5 outputs theseparated audio signal (L) to the power amplifier 55 without via thebuffer 54 (step S122).

The parent device 4-4 and the child device 4-5 perform stereoreproduction by repeatedly executing the above-described processinguntil reproduction is stopped. The parent device may be set to the Lchand the child device may be set to the Rch. As will be described indetail later, if devices which are set as the stereo pair belong to asynchronous reproduction group as a client device, since both the parentdevice and the child device receive audio signals from the masterdevice, the delayed reproduction between the parent device and the childdevice of the stereo pair is not performed.

<Description of Stereo Pair Setting and Canceling Procedure>

Next, the stereo pair setting process will be described with referenceto the flowchart illustrated in FIG. 12. FIG. 12(A) is a flowchartillustrating stereo pair setting processing of Rch. FIG. 12(B) is aflowchart illustrating Lch stereo pair setting processing of Lch. Ineach stereo pair setting processing, two audio devices 4 to be pairedare specified, and setting of the parent device and the child device andsetting of R/Lch are performed.

The stereo pair setting processing of Rch is executed when thereproduction/pause button 59B and the volume up button 59C of the audiodevice 4 to be set as the Rch of the stereo pair are simultaneouslypressed long. On the other hand, the Lch stereo pair setting process isstarted when the Reproduction/pause button 59B and the volume downbutton 59D of the audio device 4 to be set as the Lch of the stereo pairare simultaneously pressed long. That is, at the start of the stereopair setting processing, the setting of R/Lch in the stereo pair settingis determined based on which combination button is pressed long asdescribed above.

Hereinafter, as an example, a case where the reproduction/pause button59B and the volume up button 59C of the audio device 4-4 aresimultaneously pressed long time and the reproduction/pause button 59Band the volume down button 59D of the audio device 4-5 aresimultaneously pressed will be described.

The audio device 4-4 acquires its own connection position (priorityorder information) and the MAC address 1 (identification information)from the stored system management table (S130). Then, the audio device4-4 transmits the standby notification including the acquired connectionposition, the MAC address 1 and the reproduction parameter to otheraudio devices 4 in the audio system 10 by multicast (S131).

The reproduction parameter is a reproduction parameter stored in theaudio device 4-4. In the present embodiment, the reproduction parameterof the parent device are a common reproduction parameter in the parentdevice and the child device which are set as the stereo pair.

On the other hand, the audio device 4-5 receives the standbynotification transmitted by the multicast (S140), compares the receivedconnection position with its own connection position, and determines theparent-child relationship (S141). Since the audio devices 4-4 and 4-5are the leaf devices and the priorities of the audio devices 4-4 and 4-5are the same, the audio device 4-4 which is set to Rch is determined asthe parent device.

Next, the audio device 4-5 updates each setting such as the pairinginformation (S142). In a case where the audio device 4-4 becomes theparent device, in addition to the pairing information, the audio device4-5 updates its own reproduction parameter with the reproductionparameter which is received with the standby notification. On the otherhand, in a case where the audio device 4-4 becomes the child device, thereproduction parameter is not updated. Thereafter, the audio device 4-5transmits the response notification (ACK) including the parent-childrelationship, its own reproduction parameter and its own MAC address 1to the audio device 4-4 in unicast (S143).

Thereafter, the audio device 4-4 receives the response notification(S132) and updates each setting such as the pairing information in thesame manner as described above (S133). Also in this case, in a casewhere the audio device 4-5 becomes the parent device, the audio device4-4 updates its own reproduction parameter with the reproductionparameter which is received with the response notification. On the otherhand, in a case where the audio device 4-5 becomes the child device, thereproduction parameter is not updated.

Thereafter, the audio device 4-4 which is the parent device transmitsthe pairing information to the controller 1 (S134). The controller 1which has received the pairing information updates the pairinginformation in the audio control table. Instead of S134, the childdevice may transmit the pairing information to the controller 1 afterthe response notification in S143. The audio device 4-4 performsmulticast transmission in S131.

In this case, the audio device 4-4 may perform multicast transmissionrepeatedly for 5 minutes, for example, and finish the processing bytimeout if there is no response notification. Also in the audio device4-5, if the standby notification is not received for 5 minutes afterstarting the stereo pair setting processing of Lch, for example, theprocessing may be finished by a timeout.

In addition, if the stereo pair setting processings of Rch and Lch arestarted at a timing at which timeout does not occur, any one processingmay be started first.

Furthermore, in the stereo pair setting processing described above, thestandby notification including the priority information is transmitted,and the parent-child relationship is determined in the opponent's audiodevice 4. However, if each audio device 4 stores the priority orderinformation of all the audio devices 4, the parent-child relationshipmay be determined by each audio device 4. In this case, it is notnecessary to include information on the connection position in thestandby notification. In addition, it is not necessary to include theparent-child relationship in the response notification. Furthermore, ifeach audio device 4 stores the reproduction parameters of all the audiodevices 4, the reproduction parameter may not be included in the standbynotification and the response notification.

Next, the stereo pair cancel process will be described with reference tothe flowchart illustrated in FIG. 13. In the stereo pair cancelprocessing, the currently set stereo pair setting is canceled (reset).This processing is started by performing a cancel operation on theparent device or the child device. For example, in a case where thereproduction/pause button 59B and the volume up button 59C of the parentdevice or the child device are simultaneously pressed long, execution isstarted by the parent device or the child device which has been pressedlong. Hereinafter, in the above example, a case where thereproduction/pause button 59B and the volume up button 59C of the childdevice 4-5 are simultaneously pressed long will be described.

The child device 4-5 transmits a cancel notification to the parentdevice 4-4 by unicast (S150). Next, the child device 4-5 cancels thestereo pair setting (S151). Specifically, the child device resets thepairing information. That is, the pair setting of the pairinginformation is changed to have no setting. In S151, the reproductionparameter may be restored to its own reproduction parameter beforestereo setting. In this case, the reproduction parameters before stereosetting may be stored in another storage area.

On the other hand, the parent device 4-4 receives the cancelnotification (S160) and cancels the stereo pair setting as describedabove (S161). It is not necessary to notify the child device 4-5 thathas transmitted the cancel notification of the response. Accordingly,even in a case where the parent device 4-4 and the child device 4-5 aredisconnected from the network and communication is impossible, it ispossible to cancel the stereo pair setting of each other.

For example, in a case where the parent device 4-4 is disconnected fromthe network, the parent device 4-4 cannot receive the cancelnotification from the child device 4-5, but the child device 4-5 itselfcan cancel the setting as illustrated in FIG. 13. On the other hand, inthe parent device 4-4, in a case where the user simultaneously pressesthe reproduction/pause button 59B and the volume up button 59C of themaster device 4-4 long, the setting is canceled.

After canceling the pair setting, the audio device 4, which was theparent device, transmits the pair setting cancel information to thecontroller 1. The audio device 4, which is the child device, maytransmit the information to the controller 1. In addition, each of theaudio device 4, which is the parent device, and the audio device 4,which is the child device, may transmit the information to thecontroller 1. The controller 1 which has received the pair settingcancel information updates the pairing information in the audio controltable based on the pair setting cancel information.

<Description of Command Transmission and Reception Procedure in StereoPair>

Next, update processing of the reproduction parameter and transmissionprocessing of the reproduction/pause command which are executed by theaudio devices 4 set as the stereo pair will be described with referenceto FIG. 14 to FIG. 17. FIG. 14 is an explanatory diagram forillustrating a transmission mode of a command or the like between theaudio devices 4 set as the stereo pair. FIG. 15 is a flowchartillustrating the update processing of the reproduction parameter and thetransmission processing of the reproduction/pause command which areexecuted by the controller 1. FIG. 16 is a flowchart illustrating theupdate processing of the reproduction parameter and the transmissionprocessing of the reproduction/pause command which are executed by theparent device. FIG. 17 is a flowchart illustrating update processing ofthe reproduction parameter and transmission processing of thereproduction/pause command which are executed by the child device.

In the present embodiment, the user can change the setting of thereproduction parameter of the audio devices 4 set as the stereo pair byoperating the operation unit 59 (such as the volume up button 59C andthe volume down button 59D) of the parent device or the child device setas the stereo pair, or the operation unit 30 (touch panel 30A) of thecontroller 1. In a case of the stereo pair, since the parent device andthe child device have the same reproduction parameter, the changecontents are reflected in both the reproduction parameter of the parentdevice and the reproduction parameter of the child device.

The reproduction/pause command is an instruction to reproduce or pause(including momentary pause) of the content. The audio device 4 which hasreceived the reproduction/pause command starts reproduction or the likeaccording to the command. In a case where the stereo pair is set, thereproduction/pause command is generated according to the user'soperation of the operation unit 59 (reproduction/pause button 59B) ofthe parent device or the child device, or the operation unit 30 (touchpanel 30A) of the controller 1.

The update processing of the reproduction parameter and the transmissionprocessing of the reproduction/pause command in the present embodimentdiffer in processing procedure depending on whether the user's operationis performed by any one of the operation units 30 and 59 of thecontroller 1, the parent device, or the child device. In the controller1, it is possible to change the setting of the reproduction parameter ofeach audio device 4, but the operation of updating the reproductionparameter for the child device and the reproduction/pause operation onlyfor the child device is not received.

For example, a case where the audio device 4-4 is the parent device 4-4and the audio device 4-5 is the child device 4-5 will be described. Asdescribed above, the parent device 4-4 and the child device 4-5 areconsidered as one device. Therefore, in a case where the reproductionparameter is changed by the controller 1, the updated reproductionparameter and an update command are transmitted from the controller 1only to the parent device 4-4. Thereafter, the updated reproductionparameter and the update command are transmitted (transferred) from theparent device 4-4 to the child device 4-5. The update command is acommand to instruct update of the reproduction parameter.

In a case where the reproduction parameter is changed by the parentdevice 4-4, the updated reproduction parameter and the update commandare transmitted from the parent device 4-4 to the controller 1 and thechild device 4-5, respectively. In a case where the reproductionparameter is changed by the child device 4-5, the updated reproductionparameter and the update command are transmitted from the child device4-5 to only the parent device 4-4. Thereafter, the updated reproductionparameter and the update command are transmitted from the parent device4-4 to the controller 1. The same applies to the reproduction/pausecommand or the like. Accordingly, in the present embodiment, regardingthe transmission of the reproduction parameter and the command, theparent device is in charge of communication with the other devices as acommunication control unit when a plurality of audio devices 4 set asthe pair are considered as one audio apparatus.

Next, a case where the operation of changing the setting of thereproduction parameter of the parent device is performed on theabove-described controller 1 (the operation unit 30) will be describedwith reference to the flowchart of FIG. 15. Similar to FIG. 14, thedescription will be made using the parent device 4-4 and the childdevice 4-5 as an example.

The controller 1 updates the reproduction parameter based on theoperation information received by the operation unit 30 (S190). In thiscase, the reproduction parameter of the child device 4-5 is also updatedwith the same contents as the reproduction parameter of the parentdevice 4-4. Next, the controller 1 transmits the updated reproductionparameter with the update command to the parent device 4-4 (S191).

The parent device 4-4 receives the reproduction parameter and the likefrom the controller 1 (S200) and updates the currently storedreproduction parameter to the received reproduction parameter (S201).Next, the parent device 4-4 transmits the update command and thereceived reproduction parameter to the child device 4-5 (S202).

The child device 4-5 receives the reproduction parameter from the parentdevice 4-4 (S210) and updates the currently stored reproductionparameter to the received reproduction parameter (S211). As a result,the reproduction parameter changed on the controller 1 is synchronizedwith the corresponding parent device and child device.

Regarding the reproduction/pause command, similar processing isperformed, and the reproduction/pause command is transmitted to theparent device and the child device. For example, in the case of areproduction command, the reproduction status of the parent device andthe child device held in the controller is updated to “Now Reproducting”(S190). Further, the reproduction command is transmitted from thecontroller 1 to the parent device 4-4, and then the reproduction commandis transmitted from the parent device 4-4 to the child device 4-5 (S191and S202). The reproduction status information is information indicatingthe reproduction state of each audio device 4. The parent device 4-4 andthe child device 4-5 that have received the reproduction command startstereo reproduction.

Next, a case where the operation of changing the setting of thereproduction parameter is performed using the operation unit 59 of theabove-described parent device will be described with reference to theflowchart of FIG. 16. Similarly to FIG. 14, the description will be madeusing the parent device 4-4 and the child device 4-5 as an example. Inthe operation unit 59 of the parent device 4-4, only an operation inputfor changing the setting of its own reproduction parameter is received.

The parent device 4-4 updates the reproduction parameter based on theoperation information received by the operation unit (S220). Next, theparent device 4-4 transmits the updated reproduction parameter and theupdate command to the controller 1 and the child device 4-5 (S221).

The controller 1 and the child device 4-5 receive the reproductionparameter and the like from the parent device 4-4 (S230 and S240) andupdate the currently stored reproduction parameter to the receivedreproduction parameter (S231 and S241). The controller 1 updates thereproduction parameter included in the various setting information itemsin the audio control table. As a result, the reproduction parameterchanged on the parent device 4-4 is synchronized with the controller 1and the child device 4-5.

Regarding the reproduction/pause command, similar processing isperformed, and the reproduction/pause command is transmitted to thecontroller 1 and the child device 4-5. For example, in the case of areproduction command, the reproduction status of the parent device andthe child device is updated to “Now Reproducting” (S220), and areproduction command is transmitted from the parent device to the childdevice and the controller 1 (S221). The parent device 4-4 and the childdevice 4-5 start stereo reproduction.

Next, a case where an operation for changing setting of reproductionparameters is performed using the operation unit 59 of theabove-described child device will be described with reference to theflowchart of FIG. 17. Similarly to FIG. 14, the description will be madeusing the parent device 4-4 and the child device 4-5 as an example. Inaddition, since the child device 4-5 is set as the child device of thestereo pair, the operation input is received by the operation unit 59 ofthe child device 4-5 as an operation input for changing the setting ofthe reproduction parameter of the parent device 4-4.

The child device 4-5 updates the reproduction parameter based on theoperation information received by the operation unit (S250). Next, thechild device 4-5 transmits the updated reproduction parameters and theupdate command to the parent device 4-4 (S251).

The parent device 4-4 receives the reproduction parameter and the likefrom the child device 4-5 (S260) and updates the currently storedreproduction parameter to the received reproduction parameter (S261).Next, the parent device 4-4 transmits the received reproductionparameter and the update command to the controller 1 (S262).

The controller 1 receives the reproduction parameter and the like fromthe parent device 4-4 (S270) and updates the reproduction parameterincluded in the various setting information items in the currentlystored audio control table to the received reproduction parameter(S271). As a result, the reproduction parameter changed on the childdevice 4-5 is synchronized with the parent device 4-4 and the controller1.

Regarding the reproduction/pause command, similar processing isperformed, and the reproduction/pause command is transmitted to thecontroller 1 and the parent device 4-4. For example, in the case of areproduction command, the reproduction status of the parent device 4-4and the child device 4-5 is updated to “Now Reproducting” (S250), andthe reproduction command is transmitted from the child device 4-5 to theparent device 4-5 and then the reproduction command is transmitted fromthe parent device 4-4 to the controller 1 (S251 and S262). The parentdevice 4-4 and the child device 4-5 start stereo reproduction.

In addition to the reproduction/pause command, a power ON/OFF commandinstructing turning on and off the power of the portion functioning asthe reproduction device of the audio device 4 may be transmitted in thesame procedure.

<Description of Operation Procedure of Group Setting>

Next, referring to the control screen (display content of the displayunit 41) of the controller 1 (mobile phone 1) in the audio system 10illustrated in FIGS. 18 and 19, a control procedure (reproductionprocedure and group setting procedure) of the audio device 4 using thecontroller 1 will be described. FIGS. 18(A) to 18(D) are diagramsillustrating an example of the control screen at the time ofreproduction control. FIGS. 19(A) and 19(B) are diagrams illustrating anexample of the control screen at the time of group setting.

When the controller 1 is activated, the control screen is displayed onthe display unit 41. First, the initial menu screen of FIG. 18(A) isdisplayed. When the user taps a setup button 91, the touch panel 310detects the operation and the above-described setup mode is started. Inaddition, similarly, when the user taps a system connection button 92,communication with the audio device 4 in the audio system 10 is started.For example, the controller 1 communicates periodically (for example,every 10 seconds) with each audio device 4 in a polling method until thecontroller 1 is disactivated. The controller 1 receives the informationfrom each audio device 4.

First, the reproduction procedure for causing the audio device 4 toreproduce the audio source will be described. When communication withthe audio device 4 is started, a device selection screen (the listscreen) as illustrated in FIG. 18(B) is displayed on the control screen(the display unit 41) of the controller 1 (the mobile phone 1). On thedevice selection screen, a selection button (the device selectionbutton) for selecting the audio device 4 is displayed. On the deviceselection button, the device name of the audio device 4 is displayed.The device name is displayed based on the model information of the audiocontrol table.

In the example of FIG. 18(B), four device selection buttons 93 to 96 aredisplayed. The device selection button 93 is a button for selecting anAV receiver, and the audio device 4-1 is selected by this button. Thedevice selection button 94 is a button for selecting a player A, and theaudio device 4-2 is selected by this button. The device selection button95 is a button for selecting a player B, and the audio device 4-3 isselected by this button. The device selection button 96 is a button forselecting a speaker A, and the audio device 4-4 is selected by thisbutton. The user can select the audio device 4 by operating (tapping)any one of the device selection buttons 93 to 96. In the example of FIG.18(B), there are four device selection buttons 93 to 96 displayed on thecontrol screen. However, the other device selection buttons can also bedisplayed by scrolling the control screen by a touch operation.

When one of the device selection buttons is selected (tapped) by theuser, the controller 1 displays the source selection screen of theselected audio device 4. On the source selection screen, an icon button(a source selection image) indicating a reproducible (serviceable)source of the selected audio device 4 (a source which can be reproducedby the selected audio device 4) is displayed.

FIG. 18(C) illustrates the source selection screen in a case where theaudio device 4-2 is selected by tapping the device selection button 94.On the source selection screen, the icon buttons 97 to 99 indicating thesource which can be reproduced by the audio device 4-2 are displayed.

The icon button 97 is a button for selecting a CD. The icon button 98 isa button for selecting the net distribution by the distribution server6. The icon button 99 is a button for selecting FM (radio). When theuser selects (taps) one of the icon buttons, the selected source isreproduced.

For example, when the icon button 97 is selected in FIG. 18(C), thecontroller 1 transmits a command message (reproduction command) to startthe reproduction of the CD to the audio device 4-2, a reproductionscreen (Now Playing screen) of the CD as illustrated in FIG. 18(D) isdisplayed. Operation units such as a PLAY/PAUSE button and a volumeslider are displayed on this screen, and the user operates theseoperation units to execute reproduction, pause, volume control, or thelike of music (music data) of CD.

Next, a setting procedure of a group for synchronously reproducing thesame source by a plurality of audio devices 4 will be described. In thegroup setting procedure, the audio device to be the master (masterdevice) of the group and the audio device to be the client (clientdevice) are selected. The group setting procedure will be described withreference to FIG. 19.

The group setting procedure is started by selecting a link (Link) button230 illustrated in FIG. 18(B). When the link button 230 is selected, themaster device selection screen (the list screen) illustrated in FIG.19(A) is displayed. On the master device selection screen, master deviceselection buttons 121 to 125 for selecting a master which is a supplysource of an audio signal (the audio source) synchronously reproduced inthe group are displayed. On this screen, for example, when a masterdevice selection button 121 is operated, the audio device 4-1 becomesthe master of synchronous reproduction. In FIG. 19(A), for ease ofunderstanding, only five buttons 121 to 125 are displayed as masterdevice selection buttons. Other master device selection buttons can alsobe displayed by scrolling the control screen by a touch operation.

When the master is selected, the displayed screen is changed to theclient device selection screen illustrated in FIG. 19(B). On the clientdevice selection screen, client device selection buttons 225 to 228 forselecting the client of the group are displayed. When any one of theclient device selection buttons 225 to 228 is tapped, a check mark isdisplayed in a check box in the tapped button, and the tapped buttonbecomes the selected state. In FIG. 19(B), a state in which both theclient device selection buttons 225 and 226 are tapped is illustrated.In this case, the check marks are displayed in both check boxes of theclient device selection buttons 225 and 226, and the audio devices 4-2and 4-3 become the clients. Also in FIG. 19(B), for ease ofunderstanding, only four buttons 225 to 228 are displayed as clientdevice selection buttons. However, other client device selection buttonscan also be displayed by scrolling the control screen by a touchoperation.

After the above procedure, when the user operates a determination (OK)button 229, the setting of the group is completed. The information ofthis group is registered in the audio control table illustrated in FIG.5. In the audio control table illustrated in FIG. 5, the groupinformation indicating that the audio device 4-1 is master and the audiodevices 4-2 and 4-3 are the client is registered, as in the aboveexample. When the group is set, the same audio signal (the audio source)is synchronously reproduced in the audio devices 4 belonging to thegroup. The audio source is reproduced by the master audio device 4, andthe audio signal is distributed from the master to the audio devices 4set as the client. Therefore, the audio source reproduced in the groupis restricted to those which the master can reproduce.

After the group setting operation is completed, the displayed screenreturns to the device selection screen from the client device selectionscreen illustrated in FIG. 19(B). When the group is set, the groupsetting is also reflected on the device selection screen. For example,the device selection buttons 94 and 95 corresponding to the audiodevices 4-2 and 4-3 which are the clients are displayed in a state ofbeing grayed out such that the buttons cannot be selected by the user.That is, the controller 1 refers to the group information of the audiocontrol table and displays the device selection screen. On the otherhand, the device selection button 93 corresponding to the audio device4-1 which is the master can be selected. Accordingly, for example, in acase where the device selection button 93 is pressed, the sourceselection screen of the audio device 4-1 is displayed as describedabove, and after the source is selected, the reproduction screen isdisplayed. Then, with respect to the selected source, synchronousreproduction is performed by the master audio device 4-1 and the clientaudio devices 4-2 and 4-3.

Next, with reference to FIGS. 20 and 21, the device selection screen andthe group setting screen related to the audio devices 4 set as thestereo pair will be described. The display of the control screen such asthe device selection screen of the controller 1 is controlled based onthe audio device control table including the above-mentioned pairinginformation. More specifically, the audio device 4 which is the childdevice is not displayed on the control screen so as not to be operated.FIGS. 20(A) and 20(B) are diagrams illustrating an example of thecontrol screen (device selection screen) at the time of reproductioncontrol before and after stereo pair setting. FIGS. 21(A) and 21(B) arediagrams illustrating an example of the control screen (master deviceselection screen) at the time of group setting before and after stereopair setting.

For example, a case where the audio devices 4-4 and 4-5 which arespeakers are set as the stereo pair will be described. On the deviceselection screen where the audio devices 4-4 and 4-5 are not set as thestereo pair, as illustrated in FIG. 20(A), the device selection buttons96 and 100 corresponding to the audio devices 4-4 and 4-5 are displayed.Thereafter, when the stereo pair setting is performed so that the audiodevice 4-4 is set as the parent device and the audio device 4-5 is setas the child device, the pairing information of the audio device controltable is confirmed at the time of the display control. In a case wherethe pairing information indicates “child”, the device selection button100 corresponding to the audio device 4-5 is not displayed asillustrated in FIG. 20(B). That is, the audio devices 4-4 and 4-5 set asthe stereo pair are recognized by the controller 1 as one device, andonly the audio device 4-4 which is the parent device is displayed on thedevice selection screen.

As described in the stereo pair setting processing and the likeillustrated in FIG. 12, when the stereo pair setting is performed sothat the audio device 4-4 is set as the parent device and the audiodevice 4-5 is set as the child device, the pairing information of theaudio control table is updated based on the pairing informationtransmitted from the audio device 4-4 (the parent device). In addition,as described in the stereo pair cancel processing illustrated in FIG.13, the pairing information of the audio control table is updated basedon the pair setting cancel information when the stereo pair setting iscanceled.

In addition, similarly, in the master device selection screen in thegroup setting, in the state where the stereo pair is not set, asillustrated in FIG. 21(A), master device selection buttons 124 and 125corresponding to the audio devices 4-4 and 4-5 are displayed.Thereafter, in a case where the stereo pair setting is performed so thatthe audio device 4-4 is set as the parent device and the audio device4-5 is set as the child device, the pairing information of the audiocontrol table is confirmed at the time of the display control. In a casewhere the pairing information is “child”, the master device selectionbutton 125 corresponding to the audio device 4-5 is not displayed asillustrated in FIG. 21(B). The same applies to the client deviceselection screen. That is, the audio devices 4-4 and 4-5 set as thestereo pair are recognized by the controller 1 as one device, and onlythe parent device 4-4 is displayed in the selection screen in the groupsetting. In a case where the parent device belongs to the group as themaster or the client, the child device also belongs to the group. Thegroup information of the audio control table does not includeinformation indicating that the child device belongs to the group. Inaddition, in a case where the stereo pair setting is canceled, thepairing information of the audio control table is updated as describedabove, so that the display of the audio device 4 which is the childdevice is performed again.

<Description of Operation of Controller>

Next, the processing operation of the controller 1 (the control unit 20)in the audio system 10 will be described with reference to FIG. 22. Whenthe system connection button 92 is pressed by the user, this process isstarted. Apart of processing will not be illustrated.

First, the device selection screen as illustrated in FIG. 18(B) or thelike is displayed on the display unit 41 based on the system managementtable, the audio control table, the room table, or the like (S260).Then, the controller 1 waits by until any one of the device selectionbuttons is operated on the device selection screen (S261). In thisprocessing, the device selection button corresponding to the childdevice is not displayed based on the pairing information (the audiocontrol table) as described above. When any one of the buttons isoperated (YES in S261), processing corresponding to the operated buttonis performed (S262). In a case where the link button 230 is operated,group setting processing (see FIG. 23) is performed. In a case where anyone of the device selection buttons is operated, it is determinedwhether the audio device 4 selected by this operation is the client(S263). This determination is performed by referring to the groupinformation of the audio control table. In a case of the client (YES inS263), the process returns to S260.

In a case where the selected audio device 4 is not the client (NO inS263), the source selection screen of the selected audio device 4 asillustrated in FIG. 18(C) or the like is displayed on the display unit41 (S264). Specifically, the source selection screen is displayed basedon the service information of the audio control table of the selectedaudio device 4 or the like. The controller 1 waits until anyone of theicon buttons of the sources is operated (S265). When any one of the iconbuttons is operated (YES in S265), a reproduction screen correspondingto the selected icon button (the source) as illustrated in FIG. 18(D) isdisplayed, and the processing on the reproduction screen progresses.Next, referring to FIG. 23, the group setting processing executed by thecontroller 1 in the audio system 10 will be described. FIG. 23 is aflowchart illustrating the group setting processing of the controller 1(the control unit 20). When the link button 230 in the room selectionscreen is operated by the user, this process is started.

First, the master device selection screen as illustrated in FIG. 19(A)is displayed on the display unit 41 (S270), and The controller 1 waitsuntil the master is selected (S271). When the master is selected (YES inS271), the client device selection screen corresponding to the selectedmaster is displayed on the display unit 41, as illustrated in FIG. 19(B)(S272). At this time, the client device selection screen in the initialstate in which the check mark is not displayed in the check box isdisplayed. Also in the master device selection screen and the clientdevice selection screen in S270 and S272, the device selection buttoncorresponding to the child device is not displayed based on the pairinginformation (the audio control table) as described above.

Then, each time when the client is selected (YES in S273), the displayof the client device selection screen is updated (S274). That is, thescreen is updated so as to add the check icon to the check box of theselected audio device 4. If there is a check icon in the check box ofthe selected audio device 4, the screen is updated so as to delete thecheck icon. The processing of S273 and S274 is repeatedly executed untilthe selection is determined (the determination button 229 is tapped)(S275). When the selection is determined (YES in S275), the audiocontrol table is updated based on the selection result (S276).

Thereafter, based on the updated contents of the audio control table,the grouping information and the update command for updating thegrouping information are transmitted to the master and the client. Inaddition, when the synchronous reproduction group to which the audiodevice 4 belongs is canceled, a command message for resetting thegrouping information is transmitted to the audio device 4.

In a case where the parent device of the stereo pair is the master orthe client, the child device also belongs to the group. However, thegrouping information is not transmitted from the controller 1 to thechild device. As illustrated in FIGS. 24 and 25, the groupinginformation and the update command are transmitted from the parentdevice to the child device. In addition, in a case where the parentapparatus belongs to the group as the client, non-delay reproduction isperformed in the parent apparatus instead of delay reproduction asillustrated in FIG. 11, and the distribution route of the audio signalto the child apparatus is changed from the route received from theparent apparatus as illustrated in FIG. 10.

FIGS. 24 and 25 are flowcharts illustrating a process of transmittinggrouping information by the controller 1. First, a description oftransmission processing of grouping information and the update commandin a case where the parent device (and the child device) is set as theclient will be given with reference to FIG. 24. The controller 1transmits the updated grouping information to the audio device 4 whichis the master (master role and the client address) and the parent devicewhich is the client (client role and the master address) (S300). Theaudio device 4 which is the master receives the grouping information andthe like (S310) and updates its own grouping information (S311). Inaddition, the parent device which is the client receives the groupinginformation (S320) and transmits (transfers) the grouping informationand the like to the child device (sets the child device as the role ofthe client and transmits the address of the master to the child device)(S321). Thereafter, the parent device updates its own groupinginformation (ends the role as a server and becomes a client) (S322).

The child device receives the grouping information and the like (therole of the child apparatus and the address of the master) transferredfrom the parent device (S330), and determines whether or not the childdevice itself is the client (S331). The child device determines whetherthe child device itself is the client based on the received groupinginformation. In the example illustrated in FIG. 24, since the childdevice is the client (YES in S331), the set server command and the IPaddress of the child device are transmitted to the audio device 4 whichis the master (S332). Thereafter, the child device updates its owngrouping information (S333). The set server command is a command forrequesting the master to transmit the audio signal to the child devicewhich is also the client of the group (the distribution route changecommand).

The audio device 4 which is the master receives the set server commandand the like (S312) and updates the client IP addresses in the groupinginformation (S313). That is, the IP address of the child device is addedto the client IP addresses. Accordingly, in synchronous reproduction,the child device can receive the same audio signal as the parent devicefrom the audio device 4 which is the master at substantially the sametiming as the parent device, as the client.

Next, transmission processing of the grouping information and updatecommand in a case where the parent device (and the child device) is setas the master will be described with reference to FIG. 25. In the samemanner as described above, the controller 1 transmits the updatedgrouping information (role and address) and the like to the parentdevice which is the master and the audio device 4 which is the client(S300). The parent device which is the master receives the groupinginformation and the like (S320), and transmits (transfers) the groupinginformation and the like to the child device (S321). Thereafter, theparent device updates its own grouping information (S322).

The audio device 4 which is the client receives the grouping informationand the like (S310) and updates its own grouping information (S311).Further, the child device receives the grouping information and the liketransferred from the parent device (S330) and determines whether thechild device itself is the client (S331). In the example illustrated inFIG. 25, since the child device is the master (NO in S331), the childdevice does not transmit the set server command and updates its owngrouping information (S333). Accordingly, unlike the case described withreference to FIG. 24, the child device receives the audio signal fromthe parent device (without changing the distribution route).

In a case where the stereo pair setting is canceled while the childdevice belongs to a group, for example, if the child device is theclient, a reset server command is transmitted to the audio device 4which is the master, and the transmission of the synchronouslyreproduced audio signal may be stopped. In addition, if the child deviceis included in the master, there is no particular need to performanything. This is because the audio device 4, which has been the parentdevice, functions as the master.

<Description of Audio Signal Distribution Mode in Group Including StereoPair>

Next, with reference to FIG. 26, the synchronous reproduction in thegroup to which the parent device and child device belong will bedescribed. FIG. 26 is an explanatory diagram for illustrating thetransmission mode of the audio signal between the audio devices 4belonging to the group at the time of synchronous reproduction. Forcontrol of synchronous reproduction, a general technique as described inJP 2015-100085 A may be applied, and a detailed description thereof willbe omitted. Further, in the present embodiment, the number of audiodevices 4 belonging to one group can be set two or more.

In addition, as described above, in a case where the parent device isselected as the master, the parent device and the child device aretreated as masters. In addition, in a case where the parent device isselected as the client, the parent device and the child device aretreated as clients. Furthermore, as described above, the reproductionprocessing (the delay reproduction or the non-delay reproduction) of theparent apparatus is different depending on whether the parent apparatusis the master or the client.

First, an example of FIG. 26(A) will be described. In the groupillustrated in FIG. 26(A), the parent device 4-4 and the child device4-5 are the master, and the audio device 4-6 is the client.

The parent device 4-4 which is the master distributes (transmits) theaudio signal (R/L), which is the content to be synchronously reproduced,to the child device 4-5 and the audio device 4-6 which is the clientfrom the wireless LAN communication unit 56. In addition, the parentdevice 4-4 separates the audio signal (R) of the Rch from the audiosignal (R/L) and outputs the separated signal to the power amplifier 55via the buffer 54 (delay reproduction).

On the other hand, the audio device 4-6 and the child device 4-5 startreproduction at the synchronous reproduction start time specified by theparent device 4-4 which is the master. The child device 4-5 alsoseparates the audio signal (L) from the received audio signal (R/L) andoutputs the separated signal to the power amplifier 55 without via thebuffer 54 (non-delayed reproduction). As a result, the sounds of the Rchand the Lch are output from the speakers 65 and 65 of the parent device4-4 and the child device 4-5 (the stereo output is performed). In theaudio apparatus 4-6, the received audio signal (R/L) is down-mixed, forexample, and output to the power amplifier 55 without via the buffer 54,and the audio signal is output from the speaker 65 (the monaural outputis performed).

Next, an example of FIG. 26(B) will be described. In the groupillustrated in FIG. 26(B), the audio device 4-1 is master, and the audiodevice 4-2, the parent device 4-4 and the child device 4-5 are theclient. The connection mode is changed by transmitting the set servercommand from the child device to the audio device 4-1, as describedabove with reference to FIG. 24.

The audio device 4-1 which is the master distributes (transmits) theaudio signal (R/L), which is the content to be synchronously reproduced,to the audio device 4-2, the parent device 4-4, and the child device 4-5which are the client from the wireless LAN communication unit 56. Inaddition, the audio device 4-1 down-mixes the audio signal (R/L), forexample, and outputs (monaural output) to the power amplifier 55.

On the other hand, the audio device 4-2, the parent device 4-4, and thechild device 4-5 start reproduction at the synchronous reproductionstart time designated by the audio device 4-1 which is the master. Inthis case, the parent device 4-4 and the child device 4-5 separate theaudio signal (R) and the audio signal (L) from the received audio signal(R/L), respectively, and output (stereo output) the signals to the poweramplifier 55 without via the buffer 54 (non-delayed reproduction).Further, the parent device 4-4 does not transmit the audio signal (R/L)to the child device 4-14.

In a case where the parent device is the client as described above,changing the distribution route of the audio signal to the child deviceis performed in order to prevent the reproduction sound from deviatingdue to double delay by the master device and the parent device (in orderto prevent the delay time from becoming longer or becoming more severe).That is, the reason why the distribution route of the audio signal tothe child device is changed is that if the distribution route is not thedistribution route illustrated in FIG. 26(B), but the distribution routefor transmitting the audio signal from the parent device to the childdevice, the parent device needs to delay its own sound emission in orderto synchronize the reproduction with the child device, and the soundemission timing deviates from the master device that has transmitted theaudio signal on the premise that the non-delayed reproduction isperformed in the parent device (Or it is necessary to set a large delayin the master device in consideration of the distribution of the parentdevice).

As described above, since the distribution route to the child device ischanged depending on which of the master and client of the synchronousreproduction is set as the parent device, it is possible to eliminatethe occurrence of delay in stereo reproduction in the synchronousreproduction in the group composed of a plurality of reproductiondevices (the audio devices 4) including the reproduction devices (theaudio devices 4) set as the stereo pair, by changing the distributionroute of the audio signal.

<Description of Display Contents at Occurrence of Abnormality of AudioDevice>

Next, referring to FIG. 27, the display of the control screen at theoccurrence of an abnormality of the audio device 4 will be described.FIG. 27(A) is a diagram illustrating an example of the control screen(the device selection screen) at the time of reproduction control in acase where the audio device 4-1 is in an abnormal state. FIG. 27(B) is adiagram illustrating an example of a control screen (the deviceselection screen) at the time of reproduction control in a case wherethe audio device 4-5 which is the child device is in the abnormal state.

As illustrated in FIG. 18(B) or the like, the device name is displayedon the list screen of the audio devices 4. However, in a case where theaudio device 4 is in the abnormal state, in addition to the device name,information indicating that the device is in the abnormal state isdisplayed.

For example, in a case where the audio device 4-1 is in the abnormalstate, “(abnormal)” is displayed on the device selection button 93 inaddition to “AV receiver” as illustrated in FIG. 27(A). The abnormalstate includes a case where a part of functions of the audio device 4,such as the function of the reproduction processing unit of the audiodevice 4, do not operate normally and the case where the entire audiodevices 4 do not operate.

Whether the audio device 4 is abnormal or normal is determined by theaudio device 4 itself using the self-diagnosis function. In a case whereit is determined that there is an abnormality, the audio device 4transmits the information indicating that it is abnormal to thecontroller 1 via the communication using polling method. In a case wherethe entire audio device 4 does not operate, the audio device 4 cannotdetermine the abnormality. However, in this case, since thecommunication with the controller 1 is interrupted, the controller 1 maydetermine the abnormality. Specifically, the controller 1 determinesthat the audio device 4 is abnormal in a case where the communicationwith the audio device 4 which succeeded in communication cannot beperformed for a certain period. The display mode on the master selectionscreen or the like may be the same.

In addition, in a case of the audio device 4 set as the stereo pair, ifthe parent device is in the abnormal state, information indicating thatthe device is in the abnormal state is displayed as described above. Inaddition, if the child device is in the abnormal state, informationindicating that the device is in the abnormal state is displayed.However, the area to be displayed is the display area (display section)of the parent device.

For example, in a case where the audio device 4-5 which is the childdevice is in the abnormal state, as illustrated in FIG. 27(B), inaddition to the device name “speaker A” of the parent device, “{abnormal(child device)}” is displayed on the device selection button 96 of theaudio device 4-4 which is the parent device. In this case, the audiodevice 4-5, which is the child device, performs an abnormalitydetermination and transmits information indicating that it is abnormalto the controller 1 via communication using polling method. Informationindicating the abnormal state of the child device may be transmitted tothe controller 1 via the parent device. Further, the display content ofthe abnormal state of the child device is not limited to “abnormal(child device)”. For example, the display content may be “abnormal(device name)”.

Although the child device is not displayed on the list screen of theaudio devices 4 such as the device selection screen, since the abnormalstate of the child device can be displayed in the display area (displaysection) of the parent device as described above, it is possible tonotify the user of the abnormality of the child device.

Next, the stereo reproduction operation stopping processing will bedescribed with reference to the flowchart illustrated in FIG. 28. FIG.28 is a flowchart illustrating a stereo reproduction operation stoppingprocessing of the controller (control unit). In this process, inaddition to updating the display of the list screen of the audio devices4 described above, a stop command for stopping the reproductionoperation of the other audio device 4 set as the stereo pair istransmitted from the controller 1, in a case where the stereoreproduction is performed.

The audio device 4 determined to be abnormal transmits informationindicating abnormality to the controller 1 (step S350). When receivingthe information indicating the abnormality (S360), the controller 1determines whether the abnormal audio device 4 is the child device ofthe stereo pair setting (S361). For example, the determination isperformed based on the information of the audio control table. If theabnormal audio device 4 is not the child device (NO in S361), thecontroller 1 performs the normal update of the display screen (S362).Specifically, as described above, in addition to “model name”,{(abnormal)} is displayed on the device selection button or the likecorresponding to the parent device. On the other hand, if the abnormalaudio device 4 is the child apparatus (YES in S361), the update of thedisplay screen for the child device is performed (S363). Specifically,as described above, in addition to “model name”, {abnormal (childdevice)} is displayed on the device selection button or the likecorresponding to the parent device.

Thereafter, the controller 1 determines whether the audio device 4determined to be abnormal is the parent device or the child device ofthe stereo pair setting (S364). If it is determined that the audiodevice 4 is the parent device or the child device (YES in S364), thecontroller 1 transmits the stop command of the reproduction to the audiodevice 4 (parent device or child device) determined to be abnormal andthe other audio device 4 (child device or parent device) of the stereopair (S365). On the other hand, if it is determined in S364 that theaudio device 4 is neither the parent device nor the child device, theprocessing is terminated.

Then, the other audio device 4 which is the child device or the parentdevice receives the stop command of reproduction (S370) and stops thereproduction operation (S371). Accordingly, in a case where one audiodevice 4 of the stereo pair is in an abnormal state, the reproductionoperation of the other audio device 4 can be stopped. Therefore, theuser easily realizes the abnormality.

In a case where the audio device 4 included in the synchronousreproduction group is abnormal, the synchronous reproduction operationof one or more other audio devices 4 included in the group may bestopped in the same manner.

<Explanatory Note>

In the above-described embodiment, in a case where the parent device isthe client, a change command of the distribution route is transmittedfrom the child device to the master, but the command may be transmittedto the master by the parent device or the command may be transmitted byeach of the parent device and the child device. In addition, it may betransmitted from the child device to the master via the parent device.

In addition, in the above-described embodiment, only setting of onestereo pair is performed, but a plurality of stereo pairs may be set. Inaddition, the stereo pair is not limited to two audio device, and forexample, four audio devices may be set as the stereo pair.

Furthermore, as illustrated in FIG. 12, the above-described embodimenthas a configuration in which a partner (the other audio device) to beset as the stereo pair is searched, but the configuration is notparticularly limited thereto. The user may manually perform the stereopair setting such as the reproduction channel and the parent-childrelationship. In addition, the stereo pair setting may be performed bythe mobile phone.

Furthermore, in the above-described embodiments, all of the audiodevices belonging to the audio system are described as being the objectof the stereo pair setting, but the audio device which is not the objectof the stereo pair setting may be included.

Further, in the above-described embodiments, the system managementtable, the audio control table, and the like are automatically generatedwhen the audio device is connected to the network, but the configurationis not particularly limited thereto. The user may directly input thenecessary information to the controller 1 or the like.

Note that the reproduction device according to one embodiment of thepresent invention may be an audio and visual (AV) device having a videoreproduction function, and the system according to one embodiment of thepresent invention may include a system in which these devices coexist.

<Supplementary Note>

As understood from the description of the embodiment described above,various types of technical ideas including the invention described beloware disclosed in the present specification.

An audio device according to one embodiment of the present inventionincludes a network communication unit that communicates with other firstand second audio devices, a sound emission unit that emits a sound of anaudio signal, and a control unit that, in a case where a sound of onechannel of an audio signal reproduced by the first audio device isemitted by the first audio device, receives a signal of at least otherchannel of the audio signal from the first audio device via the networkcommunication unit and causes the sound emission unit to emit a sound ofthe other channel, and in a case where a sound of one channel of anaudio signal reproduced and emitted by the second audio device isemitted from the first audio device, receives a signal of at least otherchannel of the audio signal from the second audio device via the networkcommunication unit and causes the sound emission unit to emit a sound ofthe other channel.

In one embodiment of the invention, in a case where the sound emissionby the sound emission unit is stopped due to an abnormality or the like,the control unit may transmit the command, which is for instructing thefirst audio device to stop the sound emission of the audio signal, tothe first audio device via the network communication unit.

In one embodiment of the invention, in the case where the sound of onechannel of the audio signal reproduced by the first audio device isemitted by the first audio device, the control unit may receive theaudio signal from the first audio device via the network communicationunit and cause the sound emission unit to emit the sound of the otherchannel, and in the case where the sound of the one channel of the audiosignal reproduced and emitted by the second audio device is emitted bythe first audio device, the control unit may receive the audio signalfrom the second audio device via the network communication unit andcause the sound emission unit to emit the sound of the other channel.

In one embodiment of the invention, the control unit may receive acommand which is transmitted to the first audio device from a controllerand transferred by the first audio device via the network communicationunit and perform control in accordance with the command.

In one embodiment of the invention, the audio device may be a childdevice, the first audio device may be a parent device, and the secondaudio device may be an audio device other than the parent and childdevices.

An audio device according to one embodiment of the present inventionincludes a network communication unit that communicates with other firstand second audio devices, a sound emission unit that emits a sound of anaudio signal, an audio reproduction unit, and a control unit that, in acase where a sound of one channel of the audio signal reproduced by theaudio reproduction unit is emitted by the sound emission unit, transmitsa signal of at least other channel of the audio signal to the firstaudio device via the network communication unit, and in a case where asignal of at least one channel of an audio signal is received from thesecond audio device via the network communication unit and a sound isemitted by the sound emission unit, transmits a command, which is forinstructing the second audio device to transmit a signal of at leastother channel of the audio signal to the first audio device, to thesecond audio device, or transmits a command, which is for instructingthe first audio device to request the second audio device to transmit asignal of at least other channel of the audio signal, to the first audiodevice.

In one embodiment of the invention, in a case where it is detected thatthe first audio device stops the sound emission of the audio signal dueto the abnormality or the like, the control unit may instruct the soundemission unit to stop the sound emission of the audio signal.

In one embodiment of the invention, in the case where the sound of theone channel of the audio signal reproduced by the audio reproductionunit is emitted by the sound emission unit, the control unit maytransmit the audio signal to the first audio device, and in a case wherethe audio signal is received from the second audio device via thenetwork communication unit and the sound is emitted by the soundemission unit, the control unit may transmit a command, which is forinstructing the second audio device to transmit the audio signal to thefirst audio device, to the second audio device, or transmit a command,which is for instructing the first audio device to request to the secondaudio device to transmit the audio signal, to the first audio device.

In one embodiment of the invention, the network communication unit maycommunicate with a controller, and the control unit may transmit andreceive a command to and from the controller via the networkcommunication unit, and transfer the command received from thecontroller to the first audio device.

In one embodiment of the invention, the audio device may be a parentdevice, the first audio device may be a child device, and the secondaudio device may be an audio device other than the parent and childdevices.

In one embodiment of the invention, in the audio device, synchronousreproduction of the audio signal with the first and second audio devicesmay be performed.

An audio apparatus according to one embodiment of the present inventionincludes a plurality of components that are connected to each other viaa network, each of the plurality of components (audio devices) having anetwork communication unit and a sound emission unit. The component tobe a parent device among the plurality of components further includes anaudio reproduction unit. In a case where the parent device causes thesound emission unit to emit a sound of one channel of an audio signalreproduced by the audio reproduction unit, the parent device transmits asignal of at least other channel of the audio signal to a child devicethat is the other component, and the child device receives the signaltransmitted from the parent device and causes the sound emission unit toemit the sound of the other channel. In a case where the parent deviceperforms group reproduction in which a signal of at least one channel ofan audio signal, which is reproduced and emitted by another audio device(a master device) other than the parent device and the child device, isreceived from the other audio device and the sound emission isperformed, the child device receives a signal of at least other channelof the audio signal from the other audio device, and causes the soundemission unit to emit a sound of the other channel.

According to one embodiment of the invention, in a case where groupreproduction is performed in a group including a plurality of audiodevices (components: a parent device and a child device) which areconsidered as one audio apparatus and one or more other audio devices,it becomes possible to reduce a delay of the sound emission of the audiosignal in the plurality of audio devices which are considered as oneaudio apparatus by changing a distribution route of the audio signal. Inthe related art, in the audio system in which it is possible to performgroup reproduction with a plurality of audio devices, the soundsreproduced and output by the respective audio device have become thesame. For example, in a case of synchronous reproduction in a group towhich two audio devices belong, even if the content desired to bereproduced is a stereo signal, in a case where each audio device hasonly a single speaker unit (a monaural speaker), it is only possible tooutput monaural in each audio device. Therefore, for example, there is ademand for setting a plurality of audio devices as the stereo pair andconsidering them as one audio apparatus to perform the stereoreproduction. In addition, regarding the group reproduction, there isalso a demand for considering a plurality of audio devices performingthe stereo reproduction as one audio apparatus and making them belong toa group to perform the group reproduction with one or more other audiodevices belonging to the same group. However, in this case, thedistribution route of the audio signal becomes complicated, and there isa possibility that a delay occurs in stereo reproduction. In thisregard, according to one embodiment of the invention, in a case wheregroup reproduction is performed in the group including the plurality ofaudio devices (component: the parent device and the child device) whichare set as the stereo pair and are considered as one audio apparatus andone or more other audio devices, the delay in the stereo reproduction inthe plurality of audio devices which are set as the stereo pair and areconsidered as one audio apparatus can be reduced by changing thedistribution route of the audio signal. More specifically, in a casewhere, between the plurality of audio device (the parent device and thechild device) which are set as the stereo pair and are considered as oneaudio apparatus and another audio device, the group reproduction of theaudio signal to be reproduced by the other audio device is performed, itbecomes possible to reduce the delay occurring in the child device bychanging the distribution route of the audio signal to the child device.

In one embodiment of the invention, the parent device may transmit andreceive a command to and from the other audio device and transfer thecommand received from the other audio device to the child device, and ina case where the parent device performs the group reproduction, theparent device or the child device may transmit a command, which is forinstructing the other audio device to transmit the signal of at leastthe other channel of the audio signal to the child device, to the otheraudio device.

In one embodiment of the invention, in a case where the child devicestops the sound emission of the audio signal, the parent device itselfmay also stop the sound emission of the audio signal. That is, when thechild device stops the sound emission of the audio signal due to anabnormality or the like, the parent device may not continue to emitsound alone and the parent device itself also may stop the soundemission of the audio signal.

In one embodiment of the invention, in the case where the groupreproduction is performed, the audio signal which is reproduced andemitted by the other audio device may be synchronously reproduced by theparent device, the child device, and the other audio device.

In one embodiment of the invention, in the case where the parent devicecauses the sound emission unit to emit the sound of the one channel ofthe audio signal reproduced by the audio reproduction unit, the parentdevice may transmit the audio signal to the child device, and the childdevice may receive the audio signal transmitted from the parent deviceand cause the sound emission unit to emit the sound of the otherchannel, and in a case where the parent device performs groupreproduction in which the audio signal which is reproduced and emittedby the other audio device is received from the other audio device andthe sound emission is performed, the child device may receive the audiosignal from the other audio device and cause the sound emission unit toemit the sound of the other channel. That is, in a case where the parentdevice performs the group reproduction, the child device may not receivethe audio signal from the parent device but may receive the audio signalfrom the other audio device (the master device) and may emit the sound,similar to the parent device.

A control method according to one embodiment of the present inventionincludes a step of, in a case where a sound of one channel of an audiosignal reproduced by other first audio device is emitted by the firstaudio device, causing an audio device to receive a signal of at leastother channel of the audio signal from the first audio device and emit asound of the other channel by a sound emission unit, and a step of, in acase where a sound of one channel of an audio signal which is reproducedand emitted by other second audio device is emitted by the first audiodevice, causing the audio device to receive a signal of at least otherchannel of the audio signal from the second audio device and emit thesound of the other channel by the sound emission unit.

In one embodiment of the invention, a step of, in a case where the soundemission by the sound emission unit is stopped, causing the audio deviceto transmit a command, which is for instructing the first audio deviceto stop the sound emission of the audio signal, to the first audiodevice may be included.

In one embodiment of the invention, in the case where the sound of theone channel of the audio signal reproduced by the first audio device isemitted by the first audio device, the audio device may be caused toreceive the audio signal from the first audio device and emit the soundof the other channel by the sound emission unit, and in a case where thesound of the one channel of the audio signal which is reproduced andemitted by the second audio device is emitted by the first audio device,the audio device may be caused to receive the audio signal from thesecond audio device and emit the sound of the other channel by the soundemission unit.

In one embodiment of the invention, a step of causing the audio deviceto receive the command which is transmitted to the first audio devicefrom a controller and transferred by the first audio device via thenetwork communication unit and perform control in accordance with thecommand may be included.

In one embodiment of the invention, the audio device may be a childdevice, the first audio device may be a parent device, and the secondaudio device may be an audio device other than the parent and childdevices.

A control method according to one embodiment of the present inventionincludes a step of, in a case where a sound of one channel of an audiosignal reproduced by an audio device is emitted by the audio device,causing the audio device to transmit a signal of at least other channelof the audio signal to the first audio device, and a step of, in a casewhere a sound of one channel of an audio signal which is reproduced andemitted by other second audio device is emitted by the audio device,causing the audio device to transmit a command, which is for instructingthe second audio device to transmit a signal of at least other channelof the audio signal to the first audio device, to the second audiodevice, or causing the audio device to transmit a command, which is forinstructing the first audio device to request the second audio device totransmit the signal of at least the other channel to the audio signal,to the first audio device.

In one embodiment of the invention, a step of, in a case where it isdetected that the first audio device stops the sound emission of theaudio signal, causing the audio device to stop the sound emission of theaudio signal may be included.

In one embodiment of the invention, in the case where the sound of theone channel of the audio signal reproduced by the audio device isemitted by the audio device, the audio device may be caused to transmitthe audio signal to the first audio device, and in the case where thesound of the one channel of the audio signal which is reproduced andemitted by the second audio device is emitted by the audio device, theaudio device may be caused to transmit a command, which is forinstructing the second audio device to transmit the audio signal to thefirst audio device, to the second audio device, or the audio apparatusmay be caused to transmit a command, which is for instructing the firstaudio device to request the second audio apparatus to transmit the audiosignal, to the first audio device.

In one embodiment of the invention, a step of causing the audio deviceto transmit and receive the command to and from a controller and a stepof causing the audio device to transfer the command received from thecontroller to the first audio device may be included.

In one embodiment of the invention, the audio device may be a parentdevice, the first audio device may be a child device, and the secondaudio device may be an audio device other than the parent and childdevices.

In one embodiment of the invention, in the audio device, synchronousreproduction of the audio signal with the first and second audio devicesmay be performed.

In a control method according to one embodiment of the presentinvention, in a case where a component to be a parent device among aplurality of components, which are connected to each other via anetwork, each of the plurality of components including a networkcommunication unit and a sound emission unit, causes the sound emissionunit to emit a sound of one channel of an audio signal reproduced by theparent device, the parent device transmits a signal of at least otherchannel of the audio signal to a child device that is the othercomponent, the child device receives the signal transmitted from theparent device and causes the sound emission unit to emit a sound of theother channel, and in a case where the parent device performs groupreproduction in which a signal of at least one channel of an audiosignal, which is reproduced and emitted by another audio device otherthan the parent device and the child device, is received from the otheraudio device and the sound emission is performed, the child devicereceives a signal of at least other channel of the audio signal from theother audio device and causes the sound emission unit to emit a sound ofthe other channel.

In one embodiment of the invention, the parent device may transmit andreceive a command to and from the other audio device and transfer thecommand received from the other audio device to the child device, and ina case where the parent device performs the group reproduction, theparent device or the child device may transmit a command, which is forinstructing the other audio device to transmit the signal of at leastthe other channel of the audio signal to the child device, to the otheraudio device.

In one embodiment of the invention, in a case where the child devicestops the sound emission of the audio signal, the parent device itselfmay also stop the sound emission of the audio signal.

In one embodiment of the invention, in the case where the groupreproduction is performed, the audio signal which is reproduced andemitted by the other audio device may be synchronously reproduced by theparent device, the child device, and the other audio device.

In one embodiment of the invention, in the case where the parent devicecauses the sound emission unit to emit the sound of the one channel ofthe audio signal reproduced by the audio reproduction unit, the parentdevice may transmit the audio signal to the child device, and the childdevice may receive the audio signal transmitted from the parent deviceand cause the sound emission unit to emit the sound of the otherchannel, and in a case where the parent device performs groupreproduction in which the audio signal which is reproduced and emittedby the other audio device is received from the other audio device andthe sound emission is performed, the child device may receive the audiosignal from the other audio device and cause the sound emission unit toemit the sound of the other channel.

A program according to one embodiment of the present invention is aprogram to be executed by an audio device for causing the audio deviceto function as: means for, in a case where a sound of one channel of anaudio signal reproduced by other first audio device is emitted by thefirst audio device, receiving a signal of at least other channel of theaudio signal from the first audio device and causing a sound emissionunit to emit a sound of the other channel, and means for, in a casewhere a sound of one channel of an audio signal which is reproduced andemitted by other second audio device is emitted by the first audiodevice, receiving a signal of at least other channel of the audio signalfrom the second audio device and causing the sound emission unit to emita sound of the other channel. In addition, an information storage mediumaccording to another embodiment of the present invention is acomputer-readable information storage medium in which the program isrecorded.

A program according to one embodiment of the present invention is aprogram to be executed by an audio device for causing the audio deviceto function as: means for, in a case where a sound of one channel of anaudio signal reproduced by the audio device is emitted by an soundemission unit, transmitting a signal of at least other channel of theaudio signal to a first audio device, and means for, in a case where asignal of at least one channel of the audio signal which is reproducedand emitted by other second audio device is received from the secondaudio device and the sound is emitted by the sound emission unit,transmitting a command, which is for instructing the second audioapparatus to transmit a signal of at least other channel of the audiosignal to the first audio device, to the second audio device, ortransmitting a command, which is for instructing the first audio deviceto request the second audio device to transmit the signal of at leastthe other channel of the audio signal, to the first audio device. Inaddition, an information storage medium according to another embodimentof the present invention is a computer-readable information storagemedium in which the program is recorded.

While there have been described what are at present considered to becertain embodiments of the invention, it will be understood that variousmodifications may be made thereto, and it is intended that the appendedclaims cover all such modifications as fall within the true spirit andscope of the invention.

1. A control method executed by an audio device comprising: receiving,in a case where a sound of one channel of an audio signal which isreproduced and emitted by a second audio device other than the audiodevice and a first audio device is emitted by the first audio device, asignal of at least other channel of the audio signal from the secondaudio device; and causing a sound emission unit to emit a sound of theother channel.
 2. The control method according to claim 1, furthercomprising: transmitting, in a case where the sound emission by thesound emission unit is stopped, a command, which is for instructing thefirst audio device to stop the sound emission of the audio signal, tothe first audio device via the network communication unit.
 3. Thecontrol method according to claim 1, wherein, in the case where thesound of the one channel of the audio signal which is reproduced andemitted by the second audio device is emitted by the first audio device,the audio signal is received from the second audio device via thenetwork communication unit and the sound emission unit is caused to emitthe sound of the other channel.
 4. The control method according to claim1, further comprising: receiving a command which is transmitted to thefirst audio device from a controller and transferred by the first audiodevice via the network communication unit; and performing control inaccordance with the command.
 5. The control method according to claim 1,wherein the audio device is a child device, the first audio device is aparent device, and the second audio device is an audio device other thanthe parent and child devices.
 6. The control method according to claim1, further comprising: receiving, in a case where a sound of one channelof an audio signal reproduced by the first audio device is emitted bythe first audio device, a signal of at least other channel of the audiosignal from the first audio device; and causing the sound emission unitto emit a sound of the other channel.
 7. The control method according toclaim 6, wherein, in the case where the sound of the one channel of theaudio signal reproduced by the first audio device is emitted by thefirst audio device, the audio signal is received from the first audiodevice via the network communication unit and the sound emission unit iscaused to emit the sound of the other channel.
 8. An audio devicecomprising: a network communication unit; a sound emission unit; atleast one processor; and at least one memory that stores a plurality ofinstructions, which when executed by the at least one processor, causethe at least one processor to: receive, in a case where a sound of onechannel of an audio signal which is reproduced and emitted by a secondaudio device other than the audio device and a first audio device isemitted by the first audio device, a signal of at least other channel ofthe audio signal from the second audio device via the networkcommunication unit; and cause a sound emission unit to emit a sound ofthe other channel.
 9. The audio device according to claim 8, wherein theplurality of instructions further causes the at least one processor totransmit, in a case where the sound emission by the sound emission unitis stopped, a command, which is for instructing the first audio deviceto stop the sound emission of the audio signal, to the first audiodevice via the network communication unit.
 10. The audio deviceaccording to claim 8, wherein the plurality of instructions causes theat least one processor to receive, in the case where the sound of theone channel of the audio signal which is reproduced and emitted by thesecond audio device is emitted by the first audio device, the audiosignal from the second audio device via the network communication unitand cause the sound emission unit to emit the sound of the otherchannel.
 11. The audio device according to claim 8, wherein theplurality of instructions further causes the at least one processor to:receive a command which is transmitted to the first audio device from acontroller and transferred by the first audio device via the networkcommunication unit; and perform control in accordance with the command.12. The audio device according to claim 8, wherein the audio device is achild device, the first audio device is a parent device, and the secondaudio device is an audio device other than the parent and child devices.13. The audio device according to claim 8, wherein the plurality ofinstructions further causes the at least one processor to: receive, in acase where a sound of one channel of an audio signal which is reproducedby the first audio device is emitted by the first audio device, a signalof at least other channel of the audio signal from the first audiodevice via the network communication unit; and cause the sound emissionunit to emit a sound of the other channel.
 14. The audio deviceaccording to claim 13, wherein the plurality of instructions causes theat least one processor to receive, in the case where the sound of theone channel of the audio signal reproduced by the first audio device isemitted by the first audio device, the audio signal is received from thefirst audio device via the network communication unit and cause thesound emission unit to emit the sound of the other channel.
 15. Anon-transitory information storage medium in which a program to beexecuted by an audio device is recorded, the program for causing theaudio device to: receive, in a case where a sound of one channel of anaudio signal which is reproduced and emitted by a second audio deviceother than the audio device and a first audio device is emitted by thefirst audio device, a signal of at least other channel of the audiosignal from the second audio device; and cause a sound emission unit toemitting a sound of the other channel.